Introduce ChromeSupplier for async dependencies

Introduce ChromeSupplier and use it to provide OverviewModeBehavior to
the app menu and SystemUiCoordinator/NavigationBarColorController.

The ChromeSupplier allows classes to register a callback to be notified
when the wrapped dependency is available.

BUG=956260, 960129

Change-Id: If1e363be247a237b45931b1727cb76f2a6ee694b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1610205
Commit-Queue: Theresa <twellington@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661013}

chrome/android/chrome_java_sources.gni

@@ -1629,6 +1629,8 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/util/IntentUtils.java",
   "java/src/org/chromium/chrome/browser/util/KeyNavigationUtil.java",
   "java/src/org/chromium/chrome/browser/util/MathUtils.java",
+  "java/src/org/chromium/chrome/browser/util/ObservableSupplier.java",
+  "java/src/org/chromium/chrome/browser/util/ObservableSupplierImpl.java",
   "java/src/org/chromium/chrome/browser/util/PlatformUtil.java",
   "java/src/org/chromium/chrome/browser/util/UrlUtilities.java",
   "java/src/org/chromium/chrome/browser/util/ViewUtils.java",

chrome/android/chrome_junit_test_java_sources.gni

@@ -181,6 +181,7 @@ chrome_junit_test_java_sources = [
   "junit/src/org/chromium/chrome/browser/toolbar/ToolbarSecurityIconTest.java",
   "junit/src/org/chromium/chrome/browser/usage_stats/EventTrackerTest.java",
   "junit/src/org/chromium/chrome/browser/usage_stats/PageViewObserverTest.java",
+  "junit/src/org/chromium/chrome/browser/util/ObservableSupplierImplTest.java",
   "junit/src/org/chromium/chrome/browser/util/UrlUtilitiesUnitTest.java",
   "junit/src/org/chromium/chrome/browser/util/test/ShadowUrlUtilities.java",
   "junit/src/org/chromium/chrome/browser/webapps/MockWebappDataStorageClockRule.java",

chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java

@@ -148,6 +148,7 @@ import org.chromium.chrome.browser.ui.system.StatusBarColorController;
 import org.chromium.chrome.browser.util.AccessibilityUtil;
 import org.chromium.chrome.browser.util.FeatureUtilities;
 import org.chromium.chrome.browser.util.MathUtils;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 import org.chromium.chrome.browser.vr.ArDelegate;
 import org.chromium.chrome.browser.vr.ArDelegateProvider;
 import org.chromium.chrome.browser.vr.VrModuleProvider;
@@ -763,7 +764,7 @@ public abstract class ChromeActivity<C extends ChromeActivityComponent>
     public AppMenuPropertiesDelegate createAppMenuPropertiesDelegate() {
         return new AppMenuPropertiesDelegate(this, getActivityTabProvider(),
                 getMultiWindowModeStateDispatcher(), getTabModelSelector(), getToolbarManager(),
-                getWindow().getDecorView());
+                getWindow().getDecorView(), null);
     }
 
     /**
@@ -1442,6 +1443,14 @@ public abstract class ChromeActivity<C extends ChromeActivityComponent>
         return null;
     }
 
+    /**
+     * @return {@link ObservableSupplier} for the {@link OverviewModeBehavior} for this activity
+     *         if it supports an overview mode, null otherwise.
+     */
+    public @Nullable ObservableSupplier<OverviewModeBehavior> getOverviewModeBehaviorSupplier() {
+        return null;
+    }
+
     /**
      * @return Whether this Activity should initialize the BottomSheet and BottomSheetController.
      */

chrome/android/java/src/org/chromium/chrome/browser/ChromeTabbedActivity.java

@@ -149,6 +149,8 @@ import org.chromium.chrome.browser.usage_stats.UsageStatsService;
 import org.chromium.chrome.browser.util.AccessibilityUtil;
 import org.chromium.chrome.browser.util.FeatureUtilities;
 import org.chromium.chrome.browser.util.IntentUtils;
+import org.chromium.chrome.browser.util.ObservableSupplier;
+import org.chromium.chrome.browser.util.ObservableSupplierImpl;
 import org.chromium.chrome.browser.vr.VrModuleProvider;
 import org.chromium.chrome.browser.widget.OverviewListLayout;
 import org.chromium.components.feature_engagement.EventConstants;
@@ -332,6 +334,8 @@ public class ChromeTabbedActivity
             implements OverviewModeObserver, OverviewModeController {
         private OverviewModeController mInternalOverviewModeController;
         private ObserverList<OverviewModeObserver> mOverviewModeObserverList = new ObserverList<>();
+        private final ObservableSupplierImpl<OverviewModeBehavior> mOverviewModeBehaviorSupplier =
+                new ObservableSupplierImpl<>();
 
         @Override
         public boolean overviewVisible() {
@@ -392,15 +396,17 @@ public class ChromeTabbedActivity
         }
 
         /**
-         * Provide a new internal implementation to use for {@link OverviewModeController}.
-         * @param newOverviewModeController The new internal implementation to use.
+         * Provide an internal implementation to use for {@link OverviewModeController}.
+         * @param overviewModeController The internal implementation to use.
          */
-        void overrideOverviewModeController(OverviewModeController newOverviewModeController) {
+        void overrideOverviewModeController(OverviewModeController overviewModeController) {
             if (mInternalOverviewModeController != null) {
                 mInternalOverviewModeController.removeOverviewModeObserver(this);
             }
-            mInternalOverviewModeController = newOverviewModeController;
+
+            mInternalOverviewModeController = overviewModeController;
             mInternalOverviewModeController.addOverviewModeObserver(this);
+            mOverviewModeBehaviorSupplier.set(overviewModeController);
         }
     }
 
@@ -756,7 +762,10 @@ public class ChromeTabbedActivity
                         TabManagementModuleProvider.getDelegate().createGridTabSwitcher(this);
                 mOverviewModeController.overrideOverviewModeController(
                         gridTabSwitcher.getOverviewModeController());
+            } else {
+                mOverviewModeController.overrideOverviewModeController(mLayoutManager);
             }
+            mOverviewModeController.addOverviewModeObserver(this);
 
             if (ChromeFeatureList.isEnabled(ChromeFeatureList.TAB_ENGAGEMENT_REPORTING_ANDROID)) {
                 // The lifecycle of this object is managed by the lifecycle dispatcher.
@@ -916,6 +925,11 @@ public class ChromeTabbedActivity
         return mOverviewModeController;
     }
 
+    @Override
+    public @Nullable ObservableSupplier<OverviewModeBehavior> getOverviewModeBehaviorSupplier() {
+        return mOverviewModeController.mOverviewModeBehaviorSupplier;
+    }
+
     @Override
     protected AssistStatusHandler createAssistStatusHandler() {
         return new TabbedAssistStatusHandler(this);
@@ -963,8 +977,6 @@ public class ChromeTabbedActivity
                         new LayoutManagerChromePhone(compositorViewHolder, mOverviewModeController);
             }
             mLayoutManager.setEnableAnimations(DeviceClassManager.enableAnimations());
-            mOverviewModeController.overrideOverviewModeController(mLayoutManager);
-            mOverviewModeController.addOverviewModeObserver(this);
 
             // TODO(yusufo): get rid of findViewById(R.id.url_bar).
             initializeCompositorContent(mLayoutManager, findViewById(R.id.url_bar),
@@ -1649,7 +1661,8 @@ public class ChromeTabbedActivity
     public AppMenuPropertiesDelegate createAppMenuPropertiesDelegate() {
         return new TabbedAppMenuPropertiesDelegate(this, getActivityTabProvider(),
                 getMultiWindowModeStateDispatcher(), getTabModelSelector(), getToolbarManager(),
-                getWindow().getDecorView(), this);
+                getWindow().getDecorView(), this,
+                mOverviewModeController.mOverviewModeBehaviorSupplier);
     }
 
     @Override

chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenuCoordinator.java

@@ -17,6 +17,7 @@ import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.lifecycle.ActivityLifecycleDispatcher;
 import org.chromium.chrome.browser.omaha.UpdateMenuItemHelper;
 import org.chromium.chrome.browser.toolbar.ToolbarManager;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 
 /** A UI coordinator the app menu. */
 public class AppMenuCoordinator {
@@ -69,11 +70,14 @@ public class AppMenuCoordinator {
          *            It is assumed to have back_menu_id, forward_menu_id, bookmark_this_page_id.
          * @param decorView The decor {@link View}, e.g. from Window#getDecorView(), for the
          *         containing activity.
+         * @param overviewModeBehaviorSupplier An {@link ObservableSupplier} for the
+         *         {@link OverviewModeBehavior} associated with the containing activity.
          * @return AppMenuHandler for the given activity and menu resource id.
          */
         AppMenuHandler get(AppMenuPropertiesDelegate delegate, AppMenuDelegate appMenuDelegate,
                 int menuResourceId, View decorView,
-                ActivityLifecycleDispatcher activityLifecycleDispatcher);
+                ActivityLifecycleDispatcher activityLifecycleDispatcher,
+                @Nullable ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier);
     }
 
     /**
@@ -91,10 +95,10 @@ public class AppMenuCoordinator {
     private AppMenuPropertiesDelegate mAppMenuPropertiesDelegate;
     private AppMenuHandler mAppMenuHandler;
 
-    private static AppMenuHandlerFactory sAppMenuHandlerFactory =
-            (delegate, appMenuDelegate, menuResourceId, decorView, activityLifecycleDispatcher)
+    private static AppMenuHandlerFactory sAppMenuHandlerFactory = (delegate, appMenuDelegate,
+            menuResourceId, decorView, activityLifecycleDispatcher, overviewModeBehaviorSupplier)
             -> new AppMenuHandler(delegate, appMenuDelegate, menuResourceId, decorView,
-                    activityLifecycleDispatcher);
+                    activityLifecycleDispatcher, overviewModeBehaviorSupplier);
 
     /**
      * Construct a new AppMenuCoordinator.
@@ -105,10 +109,13 @@ public class AppMenuCoordinator {
      * @param appMenuDelegate The {@link AppMenuDelegate} for the containing activity.
      * @param decorView The decor {@link View}, e.g. from Window#getDecorView(), for the containing
      *         activity.
+     * @param overviewModeBehaviorSupplier An {@link ObservableSupplier} for the
+     *         {@link OverviewModeBehavior} associated with the containing activity.
      */
     public AppMenuCoordinator(Context context,
             ActivityLifecycleDispatcher activityLifecycleDispatcher,
-            MenuButtonDelegate buttonDelegate, AppMenuDelegate appMenuDelegate, View decorView) {
+            MenuButtonDelegate buttonDelegate, AppMenuDelegate appMenuDelegate, View decorView,
+            @Nullable ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
         mContext = context;
         mButtonDelegate = buttonDelegate;
         mAppMenuDelegate = appMenuDelegate;
@@ -116,7 +123,7 @@ public class AppMenuCoordinator {
 
         mAppMenuHandler = sAppMenuHandlerFactory.get(mAppMenuPropertiesDelegate, mAppMenuDelegate,
                 mAppMenuPropertiesDelegate.getAppMenuLayoutId(), decorView,
-                activityLifecycleDispatcher);
+                activityLifecycleDispatcher, overviewModeBehaviorSupplier);
 
         // TODO(twellington): Move to UpdateMenuItemHelper or common UI coordinator parent?
         mAppMenuHandler.addObserver(new AppMenuObserver() {
@@ -143,20 +150,8 @@ public class AppMenuCoordinator {
     public void destroy() {
         // Prevent the menu window from leaking.
         if (mAppMenuHandler != null) mAppMenuHandler.destroy();
-    }
 
-    /**
-     * Called when native initialization has finished to provide additional activity-scoped objects
-     * only available after native initialization.
-     *
-     * @param overviewModeBehavior The {@link OverviewModeBehavior} for the containing activity
-     *         if the current activity supports an overview mode, or null otherwise.
-     */
-    public void onNativeInitialized(@Nullable OverviewModeBehavior overviewModeBehavior) {
-        // TODO(https://crbug.com/956260): Look into providing this during construction
-        // (e.g. through an AsyncSupplier that can notify when the dependency is available).
-        mAppMenuPropertiesDelegate.onNativeInitialized(overviewModeBehavior);
-        mAppMenuHandler.onNativeInitialized(overviewModeBehavior);
+        mAppMenuPropertiesDelegate.destroy();
     }
 
     /**

chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenuHandler.java

@@ -19,6 +19,7 @@ import android.view.View;
 import android.view.WindowManager;
 import android.widget.PopupMenu;
 
+import org.chromium.base.Callback;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.metrics.RecordUserAction;
 import org.chromium.chrome.R;
@@ -26,6 +27,7 @@ import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.lifecycle.ActivityLifecycleDispatcher;
 import org.chromium.chrome.browser.lifecycle.ConfigurationChangedObserver;
 import org.chromium.chrome.browser.lifecycle.StartStopWithNativeObserver;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 import org.chromium.chrome.browser.widget.textbubble.TextBubble;
 
 import java.util.ArrayList;
@@ -47,7 +49,9 @@ public class AppMenuHandler implements StartStopWithNativeObserver, Configuratio
     private final AppMenuCoordinator.AppMenuDelegate mAppMenuDelegate;
     private final View mDecorView;
     private final ActivityLifecycleDispatcher mActivityLifecycleDispatcher;
-    private OverviewModeBehavior mOverviewModeBehavior;
+    private final @Nullable ObservableSupplier<OverviewModeBehavior> mOverviewModeBehaviorSupplier;
+    private @Nullable Callback<OverviewModeBehavior> mOverviewModeSupplierCallback;
+    private @Nullable OverviewModeBehavior mOverviewModeBehavior;
 
     /**
      * The resource id of the menu item to highlight when the menu next opens. A value of
@@ -71,10 +75,13 @@ public class AppMenuHandler implements StartStopWithNativeObserver, Configuratio
      *            activity.
      * @param activityLifecycleDispatcher The {@link ActivityLifecycleDispatcher} for the containing
      *            activity.
+     * @param overviewModeBehaviorSupplier An {@link ObservableSupplier} for the
+     *            {@link OverviewModeBehavior} associated with the containing activity.
      */
     public AppMenuHandler(AppMenuPropertiesDelegate delegate,
             AppMenuCoordinator.AppMenuDelegate appMenuDelegate, int menuResourceId, View decorView,
-            ActivityLifecycleDispatcher activityLifecycleDispatcher) {
+            ActivityLifecycleDispatcher activityLifecycleDispatcher,
+            @Nullable ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
         mAppMenuDelegate = appMenuDelegate;
         mDelegate = delegate;
         mDecorView = decorView;
@@ -85,6 +92,19 @@ public class AppMenuHandler implements StartStopWithNativeObserver, Configuratio
         mActivityLifecycleDispatcher = activityLifecycleDispatcher;
         mActivityLifecycleDispatcher.register(this);
 
+        mOverviewModeBehaviorSupplier = overviewModeBehaviorSupplier;
+        if (mOverviewModeBehavior != null) {
+            mOverviewModeSupplierCallback = overviewModeBehavior -> {
+                if (mOverviewModeBehavior != null) {
+                    mOverviewModeBehavior.removeOverviewModeObserver(this);
+                }
+
+                mOverviewModeBehavior = overviewModeBehavior;
+                mOverviewModeBehavior.addOverviewModeObserver(this);
+            };
+            mOverviewModeBehaviorSupplier.addObserver(mOverviewModeSupplierCallback);
+        }
+
         assert mHardwareButtonMenuAnchor != null
                 : "Using AppMenu requires to have menu_anchor_stub view";
     }
@@ -97,26 +117,15 @@ public class AppMenuHandler implements StartStopWithNativeObserver, Configuratio
         hideAppMenu();
 
         mActivityLifecycleDispatcher.unregister(this);
+        if (mOverviewModeBehaviorSupplier != null) {
+            mOverviewModeBehaviorSupplier.removeObserver(mOverviewModeSupplierCallback);
+        }
         if (mOverviewModeBehavior != null) {
             mOverviewModeBehavior.removeOverviewModeObserver(this);
         }
 
     }
 
-    /**
-     * Called when native initialization has finished to provide additional activity-scoped objects
-     * only available after native initialization.
-     *
-     * @param overviewModeBehavior The {@link OverviewModeBehavior} for the containing activity
-     *         if the current activity supports an overview mode, or null otherwise.
-     */
-    void onNativeInitialized(@Nullable OverviewModeBehavior overviewModeBehavior) {
-        if (overviewModeBehavior != null) {
-            mOverviewModeBehavior = overviewModeBehavior;
-            mOverviewModeBehavior.addOverviewModeObserver(this);
-        }
-    }
-
     /**
      * Notifies the menu that the contents of the menu item specified by {@code menuRowId} have
      * changed.  This should be called if icons, titles, etc. are changing for a particular menu

chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenuPropertiesDelegate.java

@@ -18,6 +18,7 @@ import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 
+import org.chromium.base.Callback;
 import org.chromium.base.CommandLine;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.metrics.RecordHistogram;
@@ -40,6 +41,7 @@ import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.toolbar.ToolbarManager;
 import org.chromium.chrome.browser.translate.TranslateBridge;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 import org.chromium.components.dom_distiller.core.DomDistillerUrlUtils;
 import org.chromium.ui.base.DeviceFormFactor;
 import org.chromium.webapk.lib.client.WebApkValidator;
@@ -57,6 +59,8 @@ public class AppMenuPropertiesDelegate {
     protected final TabModelSelector mTabModelSelector;
     protected final ToolbarManager mToolbarManager;
     protected final View mDecorView;
+    private final @Nullable ObservableSupplier<OverviewModeBehavior> mOverviewModeBehaviorSupplier;
+    private @Nullable Callback<OverviewModeBehavior> mOverviewModeSupplierCallback;
 
     protected @Nullable OverviewModeBehavior mOverviewModeBehavior;
     protected BookmarkBridge mBookmarkBridge;
@@ -71,10 +75,13 @@ public class AppMenuPropertiesDelegate {
      * @param toolbarManager The {@link ToolbarManager} for the containing activity.
      * @param decorView The decor {@link View}, e.g. from Window#getDecorView(), for the containing
      *         activity.
+     * @param overviewModeBehaviorSupplier An {@link ObservableSupplier} for the
+     *         {@link OverviewModeBehavior} associated with the containing activity.
      */
     public AppMenuPropertiesDelegate(Context context, ActivityTabProvider activityTabProvider,
             MultiWindowModeStateDispatcher multiWindowModeStateDispatcher,
-            TabModelSelector tabModelSelector, ToolbarManager toolbarManager, View decorView) {
+            TabModelSelector tabModelSelector, ToolbarManager toolbarManager, View decorView,
+            @Nullable ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
         mContext = context;
         mIsTablet = DeviceFormFactor.isNonMultiDisplayContextOnTablet(mContext);
         mActivityTabProvider = activityTabProvider;
@@ -82,17 +89,23 @@ public class AppMenuPropertiesDelegate {
         mTabModelSelector = tabModelSelector;
         mToolbarManager = toolbarManager;
         mDecorView = decorView;
+
+        mOverviewModeBehaviorSupplier = overviewModeBehaviorSupplier;
+        if (mOverviewModeBehaviorSupplier != null) {
+            mOverviewModeSupplierCallback = overviewModeBehavior -> {
+                mOverviewModeBehavior = overviewModeBehavior;
+            };
+            mOverviewModeBehaviorSupplier.addObserver(mOverviewModeSupplierCallback);
+        }
     }
 
     /**
-     * Called when native initialization has finished to provide additional activity-scoped objects
-     * only available after native initialization.
-     *
-     * @param overviewModeBehavior The {@link OverviewModeBehavior} for the containing activity
-     *         if the current activity supports an overview mode, or null otherwise.
+     * Called when the containing activity is being destroyed.
      */
-    void onNativeInitialized(@Nullable OverviewModeBehavior overviewModeBehavior) {
-        mOverviewModeBehavior = overviewModeBehavior;
+    public void destroy() {
+        if (mOverviewModeBehaviorSupplier != null) {
+            mOverviewModeBehaviorSupplier.removeObserver(mOverviewModeSupplierCallback);
+        }
     }
 
     /**

chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/OverviewModeBehavior.java

@@ -12,7 +12,7 @@ public interface OverviewModeBehavior {
     /**
      * An observer that is notified when the overview mode state changes.
      */
-    public interface OverviewModeObserver {
+    interface OverviewModeObserver {
         /**
          * Called when overview mode starts showing.
          * @param showToolbar Whether or not to show the normal toolbar when animating into overview

chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabAppMenuPropertiesDelegate.java

@@ -63,7 +63,7 @@ public class CustomTabAppMenuPropertiesDelegate extends AppMenuPropertiesDelegat
             @CustomTabsUiType final int uiType, List<String> menuEntries, boolean isOpenedByChrome,
             boolean showShare, boolean showStar, boolean showDownload, boolean isIncognito) {
         super(context, activityTabProvider, multiWindowModeStateDispatcher, tabModelSelector,
-                toolbarManager, decorView);
+                toolbarManager, decorView, null);
         mUiType = uiType;
         mMenuEntries = menuEntries;
         mIsOpenedByChrome = isOpenedByChrome;

chrome/android/java/src/org/chromium/chrome/browser/tabbed_mode/TabbedAppMenuPropertiesDelegate.java

@@ -13,11 +13,13 @@ import org.chromium.chrome.browser.appmenu.AppMenu;
 import org.chromium.chrome.browser.appmenu.AppMenuCoordinator;
 import org.chromium.chrome.browser.appmenu.AppMenuIconRowFooter;
 import org.chromium.chrome.browser.appmenu.AppMenuPropertiesDelegate;
+import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.datareduction.DataReductionMainMenuItem;
 import org.chromium.chrome.browser.multiwindow.MultiWindowModeStateDispatcher;
 import org.chromium.chrome.browser.net.spdyproxy.DataReductionProxySettings;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.toolbar.ToolbarManager;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 
 /**
  * An {@link AppMenuPropertiesDelegate} for ChromeTabbedActivity.
@@ -28,9 +30,10 @@ public class TabbedAppMenuPropertiesDelegate extends AppMenuPropertiesDelegate {
     public TabbedAppMenuPropertiesDelegate(Context context, ActivityTabProvider activityTabProvider,
             MultiWindowModeStateDispatcher multiWindowModeStateDispatcher,
             TabModelSelector tabModelSelector, ToolbarManager toolbarManager, View decorView,
-            AppMenuCoordinator.AppMenuDelegate appMenuDelegate) {
+            AppMenuCoordinator.AppMenuDelegate appMenuDelegate,
+            ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
         super(context, activityTabProvider, multiWindowModeStateDispatcher, tabModelSelector,
-                toolbarManager, decorView);
+                toolbarManager, decorView, overviewModeBehaviorSupplier);
         mAppMenuDelegate = appMenuDelegate;
     }
 

chrome/android/java/src/org/chromium/chrome/browser/ui/RootUiCoordinator.java

@@ -32,6 +32,7 @@ public class RootUiCoordinator implements Destroyable, NativeInitObserver, Infla
     private @Nullable AppMenuCoordinator mAppMenuCoordinator;
     private @Nullable ImmersiveModeManager mImmersiveModeManager;
     private SystemUiCoordinator mSystemUiCoordinator;
+    private @Nullable EmptyBackgroundViewWrapper mEmptyBackgroundViewWrapper;
 
     /**
      * Create a new {@link RootUiCoordinator} for the given activity.
@@ -51,6 +52,7 @@ public class RootUiCoordinator implements Destroyable, NativeInitObserver, Infla
         if (mSystemUiCoordinator != null) mSystemUiCoordinator.destroy();
         if (mImmersiveModeManager != null) mImmersiveModeManager.destroy();
         if (mAppMenuCoordinator != null) mAppMenuCoordinator.destroy();
+        if (mEmptyBackgroundViewWrapper != null) mEmptyBackgroundViewWrapper.destroy();
     }
 
     @Override
@@ -63,7 +65,8 @@ public class RootUiCoordinator implements Destroyable, NativeInitObserver, Infla
         if (mActivity.supportsAppMenu()) {
             mAppMenuCoordinator = new AppMenuCoordinator(mActivity,
                     mActivity.getLifecycleDispatcher(), mActivity.getToolbarManager(), mActivity,
-                    mActivity.getWindow().getDecorView());
+                    mActivity.getWindow().getDecorView(),
+                    mActivity.getOverviewModeBehaviorSupplier());
             mActivity.getToolbarManager().onAppMenuInitialized(
                     mAppMenuCoordinator.getAppMenuHandler(),
                     mAppMenuCoordinator.getAppMenuPropertiesDelegate());
@@ -73,9 +76,9 @@ public class RootUiCoordinator implements Destroyable, NativeInitObserver, Infla
 
         mImmersiveModeManager = AppHooks.get().createImmersiveModeManager(
                 mActivity.getWindow().getDecorView().findViewById(android.R.id.content));
-        mSystemUiCoordinator =
-                new SystemUiCoordinator(mActivity.getWindow(), mActivity.getTabModelSelector(),
-                        mImmersiveModeManager, mActivity.getActivityType());
+        mSystemUiCoordinator = new SystemUiCoordinator(mActivity.getWindow(),
+                mActivity.getTabModelSelector(), mImmersiveModeManager, mActivity.getActivityType(),
+                mActivity.getOverviewModeBehaviorSupplier());
 
         if (mImmersiveModeManager != null && mActivity.getToolbarManager() != null) {
             mActivity.getToolbarManager().setImmersiveModeManager(mImmersiveModeManager);
@@ -84,21 +87,17 @@ public class RootUiCoordinator implements Destroyable, NativeInitObserver, Infla
 
     @Override
     public void onFinishNativeInitialization() {
-        mSystemUiCoordinator.onNativeInitialized(mActivity.getOverviewModeBehavior());
-        if (mAppMenuCoordinator != null) {
-            mAppMenuCoordinator.onNativeInitialized(mActivity.getOverviewModeBehavior());
-        }
-
-        // TODO(twellington): Move to a TabbedRootUiCoordinator or delegate?
+        // TODO(https://crbug.com/931496): Move to a TabbedRootUiCoordinator or delegate?
+        // TODO(twellington): Supply TabModelSelector as well and move initialization earlier.
         if (mActivity.getActivityType() == ChromeActivity.ActivityType.TABBED
                 && DeviceFormFactor.isNonMultiDisplayContextOnTablet(mActivity)) {
             AppMenuHandler appMenuHandler =
                     mAppMenuCoordinator == null ? null : mAppMenuCoordinator.getAppMenuHandler();
-            EmptyBackgroundViewWrapper bgViewWrapper =
-                    new EmptyBackgroundViewWrapper(mActivity.getTabModelSelector(),
-                            mActivity.getTabCreator(false), mActivity, appMenuHandler,
-                            mActivity.getSnackbarManager(), mActivity.getOverviewModeBehavior());
-            bgViewWrapper.initialize();
+            mEmptyBackgroundViewWrapper = new EmptyBackgroundViewWrapper(
+                    mActivity.getTabModelSelector(), mActivity.getTabCreator(false), mActivity,
+                    appMenuHandler, mActivity.getSnackbarManager(),
+                    mActivity.getOverviewModeBehaviorSupplier());
+            mEmptyBackgroundViewWrapper.initialize();
         }
     }
 

chrome/android/java/src/org/chromium/chrome/browser/ui/system/NavigationBarColorController.java

@@ -16,6 +16,7 @@ import android.view.Window;
 
 import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.BuildInfo;
+import org.chromium.base.Callback;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeFeatureList;
 import org.chromium.chrome.browser.compositor.layouts.EmptyOverviewModeObserver;
@@ -27,6 +28,7 @@ import org.chromium.chrome.browser.tabmodel.TabModel;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver;
 import org.chromium.chrome.browser.ui.ImmersiveModeManager;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 import org.chromium.chrome.browser.vr.VrModeObserver;
 import org.chromium.chrome.browser.vr.VrModuleProvider;
 import org.chromium.ui.UiUtils;
@@ -43,10 +45,11 @@ class NavigationBarColorController implements VrModeObserver {
     // May be null if we return from the constructor early. Otherwise will be set.
     private final @Nullable TabModelSelector mTabModelSelector;
     private final @Nullable TabModelSelectorObserver mTabModelSelectorObserver;
+    private @Nullable ObservableSupplier<OverviewModeBehavior> mOverviewModeBehaviorSupplier;
+    private @Nullable Callback<OverviewModeBehavior> mOverviewModeSupplierCallback;
     private @Nullable OverviewModeBehavior mOverviewModeBehavior;
     private @Nullable OverviewModeObserver mOverviewModeObserver;
 
-    private boolean mInitialized;
     private boolean mUseLightNavigation;
     private boolean mOverviewModeHiding;
 
@@ -56,9 +59,12 @@ class NavigationBarColorController implements VrModeObserver {
      * @param tabModelSelector The {@link TabModelSelector} used to determine which tab model is
      *                         selected.
      * @param immersiveModeManager The {@link ImmersiveModeManager} for the containing activity.
+     * @param overviewModeBehaviorSupplier An {@link ObservableSupplier} for the
+     *         {@link OverviewModeBehavior} associated with the containing activity.
      */
     NavigationBarColorController(Window window, TabModelSelector tabModelSelector,
-            @Nullable ImmersiveModeManager immersiveModeManager) {
+            @Nullable ImmersiveModeManager immersiveModeManager,
+            ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
         assert Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1;
 
         mWindow = window;
@@ -89,7 +95,6 @@ class NavigationBarColorController implements VrModeObserver {
             return;
         }
 
-        mInitialized = true;
         mUseLightNavigation = true;
 
         mTabModelSelector = tabModelSelector;
@@ -101,6 +106,10 @@ class NavigationBarColorController implements VrModeObserver {
         };
         mTabModelSelector.addObserver(mTabModelSelectorObserver);
 
+        mOverviewModeBehaviorSupplier = overviewModeBehaviorSupplier;
+        mOverviewModeSupplierCallback = this::setOverviewModeBehavior;
+        mOverviewModeBehaviorSupplier.addObserver(mOverviewModeSupplierCallback);
+
         // TODO(https://crbug.com/806054): Observe tab loads to restrict black bottom nav to
         // incognito NTP.
 
@@ -114,6 +123,9 @@ class NavigationBarColorController implements VrModeObserver {
      */
     public void destroy() {
         if (mTabModelSelector != null) mTabModelSelector.removeObserver(mTabModelSelectorObserver);
+        if (mOverviewModeBehaviorSupplier != null) {
+            mOverviewModeBehaviorSupplier.removeObserver(mOverviewModeSupplierCallback);
+        }
         if (mOverviewModeBehavior != null) {
             mOverviewModeBehavior.removeOverviewModeObserver(mOverviewModeObserver);
         }
@@ -124,8 +136,10 @@ class NavigationBarColorController implements VrModeObserver {
      * @param overviewModeBehavior The {@link OverviewModeBehavior} used to determine whether
      *                             overview mode is showing.
      */
-    public void setOverviewModeBehavior(OverviewModeBehavior overviewModeBehavior) {
-        if (!mInitialized) return;
+    private void setOverviewModeBehavior(OverviewModeBehavior overviewModeBehavior) {
+        if (mOverviewModeBehavior != null) {
+            mOverviewModeBehavior.removeOverviewModeObserver(mOverviewModeObserver);
+        }
 
         mOverviewModeBehavior = overviewModeBehavior;
         mOverviewModeObserver = new EmptyOverviewModeObserver() {

chrome/android/java/src/org/chromium/chrome/browser/ui/system/SystemUiCoordinator.java

@@ -12,6 +12,7 @@ import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.ui.ImmersiveModeManager;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 
 /**
  * A UI coordinator that manages the system status bar and bottom navigation bar.
@@ -29,30 +30,20 @@ public class SystemUiCoordinator {
      * @param tabModelSelector The {@link TabModelSelector} for the containing activity.
      * @param immersiveModeManager The {@link ImmersiveModeManager} for the containing activity.
      * @param activityType The {@link org.chromium.chrome.browser.ChromeActivity.ActivityType} of
-     *         the containing activity
+     *         the containing activity.
+     * @param overviewModeBehaviorSupplier An {@link ObservableSupplier} for the
+     *         {@link OverviewModeBehavior} associated with the containing activity.
      */
     public SystemUiCoordinator(Window window, TabModelSelector tabModelSelector,
             @Nullable ImmersiveModeManager immersiveModeManager,
-            @ChromeActivity.ActivityType int activityType) {
+            @ChromeActivity.ActivityType int activityType,
+            @Nullable ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
+        // TODO(https://crbug.com/931496): Move to a TabbedSystemUiCoordinator or delegate?
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1
                 && activityType == ChromeActivity.ActivityType.TABBED) {
+            assert overviewModeBehaviorSupplier != null;
             mNavigationBarColorController = new NavigationBarColorController(
-                    window, tabModelSelector, immersiveModeManager);
-        }
-    }
-
-    /**
-     * Called when native initialization has finished to provide additional activity-scoped objects
-     * only available after native initialization.
-     *
-     * @param overviewModeBehavior The {@link OverviewModeBehavior} for the containing activity
-     *         if the current activity supports an overview mode, or null otherwise.
-     */
-    public void onNativeInitialized(@Nullable OverviewModeBehavior overviewModeBehavior) {
-        if (mNavigationBarColorController != null) {
-            assert overviewModeBehavior != null;
-
-            mNavigationBarColorController.setOverviewModeBehavior(overviewModeBehavior);
+                    window, tabModelSelector, immersiveModeManager, overviewModeBehaviorSupplier);
         }
     }
 

chrome/android/java/src/org/chromium/chrome/browser/util/ObservableSupplier.java

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.util;
+
+import org.chromium.base.Callback;
+import org.chromium.base.Supplier;
+
+/**
+ * ObservableSupplier wraps an asynchronously provided object E, notifying observers when the
+ * dependency is available. This allows classes dependent on E to be provided with a
+ * ObservableSupplier during construction and register a Callback<E> to be notified when the needed
+ * dependency is available.
+ *
+ * This class must only be accessed from a single thread.
+ *
+ * For classes owning the ObservableSupplier and providing it as a dependency to others, see
+ * {@link ObservableSupplierImpl}.
+ *
+ * For classes using a ObservableSupplier to receive a dependency:
+ *   - To be notified when the object is available, call {@link #addObserver(Callback)} with a
+ *     Callback to be notified when the object is available.
+ *   - If the object is already available, the Callback will be called immediately.
+ *   - The Callback may be called multiple times if the object wrapped by the ObservableSupplier
+ *     changes.
+ *
+ * @param <E> The type of the wrapped object.
+ */
+public interface ObservableSupplier<E> extends Supplier<E> {
+    /**
+     * @param obs An observer to be notified when the object owned by this supplier is available.
+     *       If the object is already available, the callback will be notified at the end of the
+     *       current message loop (so long as the object hasn't changed).
+     * @return The current object or null if it hasn't been set yet.
+     */
+    E addObserver(Callback<E> obs);
+
+    /**
+     * @param obs The observer to remove.
+     */
+    void removeObserver(Callback<E> obs);
+}
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/util/ObservableSupplierImpl.java

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.util;
+
+import android.os.Handler;
+import android.support.annotation.Nullable;
+
+import org.chromium.base.Callback;
+import org.chromium.base.ObserverList;
+
+/**
+ * Concrete implementation of {@link ObservableSupplier} to be used by classes owning the
+ * ObservableSupplier and providing it as a dependency to others.
+ *
+ * This class must only be accessed from a single thread.
+ *
+ * To use:
+ *   1. Create a new ObservableSupplierImpl<E> to pass as a dependency
+ *   2. Call {@link #set(Object)} when the real object becomes available. {@link #set(Object)} may
+ *      be called multiple times. Observers will be notified each time a new object is set.
+ *
+ * @param <E> The type of the wrapped object.
+ */
+public class ObservableSupplierImpl<E> implements ObservableSupplier<E> {
+    private final Thread mThread = Thread.currentThread();
+    private final Handler mHandler = new Handler();
+
+    private E mObject;
+    private final ObserverList<Callback<E>> mObservers = new ObserverList<>();
+
+    @Override
+    public E addObserver(Callback<E> obs) {
+        checkThread();
+        mObservers.addObserver(obs);
+
+        if (mObject != null) {
+            final E currentObject = mObject;
+            mHandler.post(() -> {
+                if (mObject != currentObject || !mObservers.hasObserver(obs)) return;
+                obs.onResult(mObject);
+            });
+        }
+
+        return mObject;
+    }
+
+    @Override
+    public void removeObserver(Callback<E> obs) {
+        checkThread();
+        mObservers.removeObserver(obs);
+    }
+
+    /**
+     * Set the object supplied by this supplier. This will notify registered callbacks that the
+     * dependency is available.
+     * @param object The object to supply.
+     */
+    public void set(E object) {
+        checkThread();
+        if (object == mObject) return;
+
+        mObject = object;
+
+        for (Callback<E> observer : mObservers) {
+            observer.onResult(mObject);
+        }
+    }
+
+    @Override
+    public @Nullable E get() {
+        checkThread();
+        return mObject;
+    }
+
+    private void checkThread() {
+        assert mThread == Thread.currentThread()
+            : "ObservableSupplierImpl must only be used on a single Thread.";
+    }
+}

chrome/android/java/src/org/chromium/chrome/browser/widget/emptybackground/EmptyBackgroundViewWrapper.java

@@ -10,6 +10,7 @@ import android.view.View;
 import android.view.View.OnAttachStateChangeListener;
 import android.view.ViewStub;
 
+import org.chromium.base.Callback;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.appmenu.AppMenuHandler;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
@@ -23,6 +24,7 @@ import org.chromium.chrome.browser.tabmodel.TabModel;
 import org.chromium.chrome.browser.tabmodel.TabModelObserver;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 
 import java.util.List;
 
@@ -35,34 +37,42 @@ public class EmptyBackgroundViewWrapper {
     private final TabCreator mTabCreator;
     private final TabModelObserver mTabModelObserver;
     private final TabModelSelectorObserver mTabModelSelectorObserver;
-    private final OverviewModeBehavior mOverviewModeBehavior;
     private final SnackbarManager mSnackbarManager;
 
+    private final ObservableSupplier<OverviewModeBehavior> mOverviewModeBehaviorSupplier;
+    private final Callback<OverviewModeBehavior> mOverviewModeSupplierCallback;
+    private @Nullable OverviewModeBehavior mOverviewModeBehavior;
+
     private EmptyBackgroundViewTablet mBackgroundView;
     private final @Nullable AppMenuHandler mMenuHandler;
 
     /**
      * Creates a {@link EmptyBackgroundViewWrapper} instance that will lazily inflate.
-     * @param selector             A {@link TabModelSelector} that will be used to query system
-     *                             state.
-     * @param tabCreator           A {@link TabCreator} that will be used to open the New Tab Page.
-     * @param activity             An {@link Activity} that represents a parent of the
-     *                             {@link android.view.ViewStub}.
-     * @param menuHandler          A {@link AppMenuHandler} to handle menu touch events.
-     * @param snackbarManager      The {@link SnackbarManager} to show the undo snackbar when the
-     *                             empty background is visible.
-     * @param overviewModeBehavior A {@link OverviewModeBehavior} instance to detect when the app
-     *                             is in overview mode.
+     * @param selector A {@link TabModelSelector} that will be used to query system state.
+     * @param tabCreator A {@link TabCreator} that will be used to open the New Tab Page.
+     * @param activity An {@link Activity} that represents a parent of th
+     *         {@link android.view.ViewStub}.
+     * @param menuHandler A {@link AppMenuHandler} to handle menu touch events.
+     * @param snackbarManager The {@link SnackbarManager} to show the undo snackbar when the empty
+     *         background is visible.
+     * @param overviewModeBehaviorSupplier An {@link ObservableSupplier} for the
+     *         {@link OverviewModeBehavior} associated with the containing activity.
      */
     public EmptyBackgroundViewWrapper(TabModelSelector selector, TabCreator tabCreator,
             Activity activity, @Nullable AppMenuHandler menuHandler,
-            SnackbarManager snackbarManager, OverviewModeBehavior overviewModeBehavior) {
+            SnackbarManager snackbarManager,
+            ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
         mActivity = activity;
         mMenuHandler = menuHandler;
         mTabModelSelector = selector;
         mTabCreator = tabCreator;
         mSnackbarManager = snackbarManager;
-        mOverviewModeBehavior = overviewModeBehavior;
+
+        mOverviewModeBehaviorSupplier = overviewModeBehaviorSupplier;
+        mOverviewModeSupplierCallback =
+                overviewModeBehavior -> mOverviewModeBehavior = overviewModeBehavior;
+        mOverviewModeBehaviorSupplier.addObserver(mOverviewModeSupplierCallback);
+
         mTabModelObserver = new EmptyTabModelObserver() {
             @Override
             public void didAddTab(Tab tab, @TabLaunchType int type) {
@@ -102,6 +112,13 @@ public class EmptyBackgroundViewWrapper {
         };
     }
 
+    /**
+     * Called when the containing activity is being destroyed.
+     */
+    public void destroy() {
+        mOverviewModeBehaviorSupplier.removeObserver(mOverviewModeSupplierCallback);
+    }
+
     /**
      * Initialize the wrapper to listen for the proper notifications.
      */
@@ -161,7 +178,8 @@ public class EmptyBackgroundViewWrapper {
         // 1. There are no tabs in the normal TabModel AND
         // 2. Overview mode is not showing AND
         // 3. We're in the normal TabModel OR there are no tabs present in either model
-        return model.getCount() == 0 && !mOverviewModeBehavior.overviewVisible()
+        return model.getCount() == 0
+                && (mOverviewModeBehavior == null || !mOverviewModeBehavior.overviewVisible())
                 && (!incognitoSelected || isIncognitoEmpty);
     }
 }

chrome/android/javatests/src/org/chromium/chrome/browser/appmenu/AppMenuTest.java

@@ -27,7 +27,9 @@ import org.chromium.base.test.util.UrlUtils;
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.ChromeTabbedActivity;
+import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.lifecycle.ActivityLifecycleDispatcher;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 import org.chromium.chrome.test.ChromeActivityTestRule;
 import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 import org.chromium.chrome.test.util.ChromeTabUtils;
@@ -62,9 +64,10 @@ public class AppMenuTest {
          */
         public AppMenuHandlerForTest(AppMenuPropertiesDelegate delegate,
                 AppMenuCoordinator.AppMenuDelegate appMenuDelegate, int menuResourceId,
-                View decorView, ActivityLifecycleDispatcher activityLifecycleDispatcher) {
-            super(delegate, appMenuDelegate, menuResourceId, decorView,
-                    activityLifecycleDispatcher);
+                View decorView, ActivityLifecycleDispatcher activityLifecycleDispatcher,
+                ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
+            super(delegate, appMenuDelegate, menuResourceId, decorView, activityLifecycleDispatcher,
+                    overviewModeBehaviorSupplier);
         }
 
         @Override
@@ -79,10 +82,11 @@ public class AppMenuTest {
         InstrumentationRegistry.getInstrumentation().setInTouchMode(false);
 
         AppMenuCoordinator.setAppMenuHandlerFactoryForTesting(
-                (delegate, appMenuDelegate, menuResourceId, decorView,
-                        activityLifecycleDispatcher) -> {
+                (delegate, appMenuDelegate, menuResourceId, decorView, activityLifecycleDispatcher,
+                        overviewModeBehaviorSupplier) -> {
                     mAppMenuHandler = new AppMenuHandlerForTest(delegate, appMenuDelegate,
-                            menuResourceId, decorView, activityLifecycleDispatcher);
+                            menuResourceId, decorView, activityLifecycleDispatcher,
+                            overviewModeBehaviorSupplier);
                     return mAppMenuHandler;
                 });
 

chrome/android/javatests/src/org/chromium/chrome/browser/appmenu/DataSaverAppMenuTest.java

@@ -20,8 +20,10 @@ import org.chromium.base.test.util.RetryOnFailure;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.ChromeSwitches;
+import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.lifecycle.ActivityLifecycleDispatcher;
 import org.chromium.chrome.browser.net.spdyproxy.DataReductionProxySettings;
+import org.chromium.chrome.browser.util.ObservableSupplier;
 import org.chromium.chrome.test.ChromeActivityTestRule;
 import org.chromium.chrome.test.ChromeJUnit4ClassRunner;
 import org.chromium.chrome.test.util.browser.Features.EnableFeatures;
@@ -52,9 +54,10 @@ public class DataSaverAppMenuTest {
          */
         public AppMenuHandlerForTest(AppMenuPropertiesDelegate delegate,
                 AppMenuCoordinator.AppMenuDelegate appMenuDelegate, int menuResourceId,
-                View decorView, ActivityLifecycleDispatcher activityLifecycleDispatcher) {
-            super(delegate, appMenuDelegate, menuResourceId, decorView,
-                    activityLifecycleDispatcher);
+                View decorView, ActivityLifecycleDispatcher activityLifecycleDispatcher,
+                ObservableSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier) {
+            super(delegate, appMenuDelegate, menuResourceId, decorView, activityLifecycleDispatcher,
+                    overviewModeBehaviorSupplier);
             mDelegate = delegate;
         }
 
@@ -83,10 +86,11 @@ public class DataSaverAppMenuTest {
     @Before
     public void setUp() throws Exception {
         AppMenuCoordinator.setAppMenuHandlerFactoryForTesting(
-                (delegate, appMenuDelegate, menuResourceId, decorView,
-                        activityLifecycleDispatcher) -> {
+                (delegate, appMenuDelegate, menuResourceId, decorView, activityLifecycleDispatcher,
+                        overviewModeBehaviorSupplier) -> {
                     mAppMenuHandler = new AppMenuHandlerForTest(delegate, appMenuDelegate,
-                            menuResourceId, decorView, activityLifecycleDispatcher);
+                            menuResourceId, decorView, activityLifecycleDispatcher,
+                            overviewModeBehaviorSupplier);
                     return mAppMenuHandler;
                 });
 

chrome/android/junit/src/org/chromium/chrome/browser/util/ObservableSupplierImplTest.java

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.util;
+
+import android.os.Handler;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.annotation.Config;
+
+import org.chromium.base.Callback;
+import org.chromium.base.test.BaseRobolectricTestRunner;
+
+/**
+ * Unit tests for {@link ObservableSupplierImpl}.
+ */
+@RunWith(BaseRobolectricTestRunner.class)
+@Config(manifest = Config.NONE)
+public class ObservableSupplierImplTest {
+    private static final String TEST_STRING_1 = "Test";
+    private static final String TEST_STRING_2 = "Test2";
+
+    private int mCallCount;
+    private String mLastSuppliedString;
+    private ObservableSupplierImpl<String> mSupplier = new ObservableSupplierImpl<>();
+
+    @Test
+    public void testObserverNotification_SetMultiple() {
+        Callback<String> supplierObserver = result -> {
+            mCallCount++;
+            mLastSuppliedString = result;
+        };
+
+        mSupplier.addObserver(supplierObserver);
+        checkState(0, null, null, "before setting first string.");
+
+        mSupplier.set(TEST_STRING_1);
+        checkState(1, TEST_STRING_1, TEST_STRING_1, "after setting first string.");
+
+        mSupplier.set(TEST_STRING_2);
+        checkState(2, TEST_STRING_2, TEST_STRING_2, "after setting second string.");
+
+        mSupplier.set(null);
+        checkState(3, null, null, "after setting third string.");
+    }
+
+    @Test
+    public void testObserverNotification_SetSame() {
+        Callback<String> supplierObserver = result -> {
+            mCallCount++;
+            mLastSuppliedString = result;
+        };
+
+        mSupplier.addObserver(supplierObserver);
+        checkState(0, null, null, "before setting first string.");
+
+        mSupplier.set(TEST_STRING_1);
+        checkState(1, TEST_STRING_1, TEST_STRING_1, "after setting first string.");
+
+        mSupplier.set(TEST_STRING_1);
+        checkState(1, TEST_STRING_1, TEST_STRING_1, "after resetting first string.");
+    }
+
+    @Test
+    public void testObserverNotification_RemoveObserver() {
+        Callback<String> supplierObserver = result -> {
+            mCallCount++;
+            mLastSuppliedString = result;
+        };
+
+        mSupplier.addObserver(supplierObserver);
+        checkState(0, null, null, "before setting first string.");
+
+        mSupplier.set(TEST_STRING_1);
+        checkState(1, TEST_STRING_1, TEST_STRING_1, "after setting first string.");
+
+        mSupplier.removeObserver(supplierObserver);
+
+        mSupplier.set(TEST_STRING_2);
+        checkState(1, TEST_STRING_1, TEST_STRING_2, "after setting second string.");
+    }
+
+    @Test
+    public void testObserverNotification_RegisterObserverAfterSet() {
+        Handler handler = new Handler();
+        handler.post(() -> {
+            mSupplier.set(TEST_STRING_1);
+            checkState(0, null, TEST_STRING_1, "after setting first string.");
+
+            Callback<String> supplierObserver = new Callback<String>() {
+                @Override
+                public void onResult(String result) {
+                    mCallCount++;
+                    mLastSuppliedString = result;
+                }
+            };
+
+            mSupplier.addObserver(supplierObserver);
+
+            checkState(0, null, TEST_STRING_1, "after setting observer.");
+        });
+
+        handler.post(() -> checkState(1, TEST_STRING_1, TEST_STRING_1, "in second message loop."));
+    }
+
+    @Test
+    public void testObserverNotification_RegisterObserverAfterSetThenSetAgain() {
+        Handler handler = new Handler();
+        handler.post(() -> {
+            mSupplier.set(TEST_STRING_1);
+            checkState(0, null, TEST_STRING_1, "after setting first string.");
+
+            Callback<String> supplierObserver = new Callback<String>() {
+                @Override
+                public void onResult(String result) {
+                    mCallCount++;
+                    mLastSuppliedString = result;
+                }
+            };
+
+            mSupplier.addObserver(supplierObserver);
+
+            checkState(0, null, TEST_STRING_1, "after setting observer.");
+
+            mSupplier.set(TEST_STRING_2);
+            checkState(1, TEST_STRING_2, TEST_STRING_2, "after setting second string.");
+        });
+
+        handler.post(() -> checkState(1, TEST_STRING_2, TEST_STRING_2, "in second message loop."));
+    }
+
+    @Test
+    public void testObserverNotification_RegisterObserverAfterSetThenRemove() {
+        Handler handler = new Handler();
+        handler.post(() -> {
+            mSupplier.set(TEST_STRING_1);
+            checkState(0, null, TEST_STRING_1, "after setting first string.");
+
+            Callback<String> supplierObserver = new Callback<String>() {
+                @Override
+                public void onResult(String result) {
+                    mCallCount++;
+                    mLastSuppliedString = result;
+                }
+            };
+
+            mSupplier.addObserver(supplierObserver);
+
+            checkState(0, null, TEST_STRING_1, "after setting observer.");
+
+            mSupplier.removeObserver(supplierObserver);
+        });
+
+        handler.post(() -> checkState(0, null, TEST_STRING_1, "in second message loop."));
+    }
+
+    @Test
+    public void testObserverNotification_RemoveObserverInsideCallback() {
+        Callback<String> supplierObserver = new Callback<String>() {
+            @Override
+            public void onResult(String result) {
+                mCallCount++;
+                mLastSuppliedString = result;
+                mSupplier.removeObserver(this);
+            }
+        };
+
+        mSupplier.addObserver(supplierObserver);
+        checkState(0, null, null, "before setting first string.");
+
+        mSupplier.set(TEST_STRING_1);
+        checkState(1, TEST_STRING_1, TEST_STRING_1, "after setting first string.");
+
+        mSupplier.set(TEST_STRING_2);
+        checkState(1, TEST_STRING_1, TEST_STRING_2, "after setting second string.");
+    }
+
+    private void checkState(int expectedCallCount, String expectedLastSuppliedString,
+            String expectedStringFromGet, String assertDescription) {
+        Assert.assertEquals(
+                "Incorrect call count " + assertDescription, expectedCallCount, mCallCount);
+        Assert.assertEquals("Incorrect last supplied string " + assertDescription,
+                expectedLastSuppliedString, mLastSuppliedString);
+        Assert.assertEquals(
+                "Incorrect #get() " + assertDescription, expectedStringFromGet, mSupplier.get());
+    }
+}