Toolbar: Remove some outbound dependencies

This CL removes some outbound dependencies of TopToolbarCoordinator:

1. IdentityDiscController
  - observer registration is now managed by ToolbarManager
  - Supplier is passed to StartSurface instead

2. compositor.Invalidator.Client
   compositor.layouts.LayoutUpdateHost
  - Uses a simple Runnable instead of the interface

3. HomepageManager
  - observer registration is now managed by ToolbarManager

Bug: 1127732

Change-Id: I52a2a714fa180637ce8418559956ec55e803da0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2423144Reviewed-by: Patrick Noland <pnoland@chromium.org>
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Jinsuk Kim <jinsukkim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#810393}

chrome/android/java/src/org/chromium/chrome/browser/compositor/CompositorViewHolder.java

@@ -46,7 +46,6 @@ import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ActivityTabProvider;
 import org.chromium.chrome.browser.browser_controls.BrowserControlsStateProvider;
 import org.chromium.chrome.browser.browser_controls.BrowserControlsUtils;
-import org.chromium.chrome.browser.compositor.Invalidator.Client;
 import org.chromium.chrome.browser.compositor.layouts.LayoutManager;
 import org.chromium.chrome.browser.compositor.layouts.LayoutManagerHost;
 import org.chromium.chrome.browser.compositor.layouts.LayoutRenderHost;
@@ -137,8 +136,7 @@ public class CompositorViewHolder extends FrameLayout
 
     private int mPendingFrameCount;
 
-    private final ArrayList<Invalidator.Client> mPendingInvalidations =
-            new ArrayList<>();
+    private final ArrayList<Runnable> mPendingInvalidations = new ArrayList<>();
     private boolean mSkipInvalidation;
 
     /**
@@ -1402,11 +1400,11 @@ public class CompositorViewHolder extends FrameLayout
     }
 
     @Override
-    public void deferInvalidate(Client client) {
+    public void deferInvalidate(Runnable clientInvalidator) {
         if (mPendingFrameCount <= 0) {
-            client.doInvalidate();
-        } else if (!mPendingInvalidations.contains(client)) {
-            mPendingInvalidations.add(client);
+            clientInvalidator.run();
+        } else if (!mPendingInvalidations.contains(clientInvalidator)) {
+            mPendingInvalidations.add(clientInvalidator);
         }
     }
 
@@ -1414,7 +1412,7 @@ public class CompositorViewHolder extends FrameLayout
         if (mPendingInvalidations.isEmpty()) return;
         TraceEvent.instant("CompositorViewHolder.flushInvalidation");
         for (int i = 0; i < mPendingInvalidations.size(); i++) {
-            mPendingInvalidations.get(i).doInvalidate();
+            mPendingInvalidations.get(i).run();
         }
         mPendingInvalidations.clear();
     }

chrome/android/java/src/org/chromium/chrome/browser/compositor/Invalidator.java

@@ -8,16 +8,6 @@ package org.chromium.chrome.browser.compositor;
  * The {@link Invalidator} invalidates a client when it is the right time.
  */
 public class Invalidator {
-    /**
-     * Interface for the client that gets invalidated.
-     */
-    public interface Client {
-        /**
-         * Do the invalidation.
-         */
-        void doInvalidate();
-    }
-
     /**
      * Interface for the host that drives the invalidations.
      */
@@ -25,9 +15,9 @@ public class Invalidator {
         /**
          * Requests an invalidation of the view.
          *
-         * @param view The {@link View} to invalidate.
+         * @param invalidator {@link Runnable} that invalidates the view.
          */
-        void deferInvalidate(Client view);
+        void deferInvalidate(Runnable invalidator);
     }
 
     private Host mHost;
@@ -43,13 +33,13 @@ public class Invalidator {
      * Invalidates either immediately (if no host is specified) or at time
      * triggered by the host.
      *
-     * @param client The {@link Client} to invalidate, most likely a view.
+     * @param invalidator The {@link Runnable} performing invalidation.
      */
-    public void invalidate(Client client) {
+    public void invalidate(Runnable invalidator) {
         if (mHost != null) {
-            mHost.deferInvalidate(client);
+            mHost.deferInvalidate(invalidator);
         } else {
-            client.doInvalidate();
+            invalidator.run();
         }
     }
 }

chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarManager.java

@@ -24,6 +24,7 @@ import org.chromium.base.Callback;
 import org.chromium.base.CallbackController;
 import org.chromium.base.TraceEvent;
 import org.chromium.base.supplier.ObservableSupplier;
+import org.chromium.base.supplier.ObservableSupplierImpl;
 import org.chromium.base.supplier.OneshotSupplier;
 import org.chromium.base.supplier.Supplier;
 import org.chromium.chrome.R;
@@ -50,6 +51,7 @@ import org.chromium.chrome.browser.findinpage.FindToolbarManager;
 import org.chromium.chrome.browser.findinpage.FindToolbarObserver;
 import org.chromium.chrome.browser.fullscreen.FullscreenManager;
 import org.chromium.chrome.browser.fullscreen.FullscreenOptions;
+import org.chromium.chrome.browser.homepage.HomepageManager;
 import org.chromium.chrome.browser.identity_disc.IdentityDiscController;
 import org.chromium.chrome.browser.ntp.FakeboxDelegate;
 import org.chromium.chrome.browser.ntp.IncognitoNewTabPage;
@@ -83,6 +85,7 @@ import org.chromium.chrome.browser.toolbar.top.Toolbar;
 import org.chromium.chrome.browser.toolbar.top.ToolbarActionModeCallback;
 import org.chromium.chrome.browser.toolbar.top.ToolbarControlContainer;
 import org.chromium.chrome.browser.toolbar.top.ToolbarLayout;
+import org.chromium.chrome.browser.toolbar.top.ToolbarPhone;
 import org.chromium.chrome.browser.toolbar.top.TopToolbarCoordinator;
 import org.chromium.chrome.browser.toolbar.top.ViewShiftingActionBarDelegate;
 import org.chromium.chrome.browser.ui.TabObscuringHandler;
@@ -121,6 +124,10 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
     private final ToolbarControlContainer mControlContainer;
     private final BrowserControlsStateProvider.Observer mBrowserControlsObserver;
     private final FullscreenManager.Observer mFullscreenObserver;
+    private final ObservableSupplierImpl<Boolean> mHomeButtonVisibilitySupplier =
+            new ObservableSupplierImpl<>();
+    private final ObservableSupplierImpl<Boolean> mIdentityDiscStateSupplier =
+            new ObservableSupplierImpl<>();
 
     private BottomControlsCoordinator mBottomControlsCoordinator;
     private TabModelSelector mTabModelSelector;
@@ -142,6 +149,7 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
     private BookmarkBridge.BookmarkModelObserver mBookmarksObserver;
     private FindToolbarObserver mFindToolbarObserver;
     private OverviewModeObserver mOverviewModeObserver;
+    private @OverviewModeState int mOverviewModeState = OverviewModeState.NOT_SHOWN;
 
     private OverviewModeBehavior mOverviewModeBehavior;
     private OneshotSupplier<OverviewModeBehavior> mOverviewModeBehaviorSupplier;
@@ -160,6 +168,7 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
     private final LoadProgressCoordinator mProgressBarCoordinator;
     private final ToolbarTabControllerImpl mToolbarTabController;
     private MenuButtonCoordinator mMenuButtonCoordinator;
+    private HomepageManager.HomepageStateListener mHomepageStateListener;
 
     private BrowserStateBrowserControlsVisibilityDelegate mControlsVisibilityDelegate;
     private int mFullscreenFocusToken = TokenHolder.INVALID_TOKEN;
@@ -309,17 +318,13 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
                 mActivity.getCompositorViewHolder()::requestFocus, shouldShowUpdateBadge,
                 mActivity::isInOverviewMode, overviewModeThemeColorProvider, R.id.none);
 
-        mToolbar = new TopToolbarCoordinator(controlContainer, toolbarLayout,
-                identityDiscController, mLocationBarModel, mToolbarTabController,
-                new UserEducationHelper(mActivity, mHandler), buttonDataProviders,
-                mOverviewModeBehaviorSupplier, browsingModeThemeColorProvider,
-                mAppThemeColorProvider, mMenuButtonCoordinator, startSurfaceMenuButtonCoordinator,
-                mMenuButtonCoordinator.getMenuButtonHelperSupplier(), mActivity,
-                mTabModelSelectorSupplier);
+        mToolbar = createTopToolbarCoordinator(controlContainer, toolbarLayout, buttonDataProviders,
+                browsingModeThemeColorProvider, startSurfaceMenuButtonCoordinator, invalidator,
+                identityDiscController);
+
         mActionModeController =
                 new ActionModeController(mActivity, mActionBarDelegate, toolbarActionModeCallback);
 
-        mToolbar.setPaintInvalidator(invalidator);
         mActionModeController.setTabStripHeight(mToolbar.getTabStripHeight());
         mLocationBar = mToolbar.getLocationBar();
         mLocationBar.setProfileSupplier(profileSupplier);
@@ -573,6 +578,7 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
             public void onOverviewModeStateChanged(
                     @OverviewModeState int overviewModeState, boolean showTabSwitcherToolbar) {
                 assert StartSurfaceConfiguration.isStartSurfaceEnabled();
+                mOverviewModeState = overviewModeState;
                 mToolbar.updateTabSwitcherToolbarState(showTabSwitcherToolbar);
             }
 
@@ -618,6 +624,36 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
         TraceEvent.end("ToolbarManager.ToolbarManager");
     }
 
+    private TopToolbarCoordinator createTopToolbarCoordinator(
+            ToolbarControlContainer controlContainer, ToolbarLayout toolbarLayout,
+            List<ButtonDataProvider> buttonDataProviders,
+            ThemeColorProvider browsingModeThemeColorProvider,
+            MenuButtonCoordinator startSurfaceMenuButtonCoordinator, Invalidator invalidator,
+            IdentityDiscController identityDiscController) {
+        TopToolbarCoordinator toolbar = new TopToolbarCoordinator(controlContainer, toolbarLayout,
+                mLocationBarModel, mToolbarTabController,
+                new UserEducationHelper(mActivity, mHandler), buttonDataProviders,
+                mOverviewModeBehaviorSupplier, browsingModeThemeColorProvider,
+                mAppThemeColorProvider, mMenuButtonCoordinator, startSurfaceMenuButtonCoordinator,
+                mMenuButtonCoordinator.getMenuButtonHelperSupplier(), mTabModelSelectorSupplier,
+                mHomeButtonVisibilitySupplier, mIdentityDiscStateSupplier, (client) -> {
+                    if (invalidator != null) {
+                        invalidator.invalidate(client);
+                    } else {
+                        client.run();
+                    }
+                }, () -> identityDiscController.getForStartSurface(mOverviewModeState));
+        mHomepageStateListener =
+                () -> mHomeButtonVisibilitySupplier.set(HomepageManager.isHomepageEnabled());
+        HomepageManager.getInstance().addListener(mHomepageStateListener);
+        if (toolbarLayout instanceof ToolbarPhone
+                && StartSurfaceConfiguration.isStartSurfaceEnabled()) {
+            identityDiscController.addObserver(
+                    (canShowHint) -> mIdentityDiscStateSupplier.set(canShowHint));
+        }
+        return toolbar;
+    }
+
     /**
      * Called when the contextual action bar's visibility has changed (i.e. the widget shown
      * when you can copy/paste text after long press).
@@ -693,7 +729,7 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
                 TabSwitcherActionMenuCoordinator.createOnLongClickListener(
                         (id) -> mActivity.onOptionsItemSelected(id, null));
 
-        mToolbar.initializeWithNative(layoutManager, tabSwitcherClickHandler,
+        mToolbar.initializeWithNative(layoutManager::requestUpdate, tabSwitcherClickHandler,
                 tabSwitcherLongClickHandler, newTabClickHandler, bookmarkClickHandler,
                 customTabsBackClickHandler);
 
@@ -843,6 +879,8 @@ public class ToolbarManager implements UrlFocusChangeListener, ThemeColorObserve
             mLayoutManager = null;
         }
 
+        HomepageManager.getInstance().removeListener(mHomepageStateListener);
+
         if (mBottomControlsCoordinator != null) {
             mBottomControlsCoordinator.destroy();
             mBottomControlsCoordinator = null;

chrome/android/java/src/org/chromium/chrome/browser/toolbar/top/StartSurfaceToolbarCoordinator.java

@@ -13,13 +13,15 @@ import androidx.annotation.VisibleForTesting;
 
 import org.chromium.base.CallbackController;
 import org.chromium.base.library_loader.LibraryLoader;
+import org.chromium.base.supplier.ObservableSupplier;
 import org.chromium.base.supplier.OneshotSupplier;
+import org.chromium.base.supplier.Supplier;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ThemeColorProvider;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
-import org.chromium.chrome.browser.identity_disc.IdentityDiscController;
 import org.chromium.chrome.browser.incognito.IncognitoUtils;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
+import org.chromium.chrome.browser.toolbar.ButtonData;
 import org.chromium.chrome.browser.toolbar.IncognitoStateProvider;
 import org.chromium.chrome.browser.toolbar.TabCountProvider;
 import org.chromium.chrome.browser.toolbar.TabSwitcherButtonCoordinator;
@@ -53,9 +55,11 @@ public class StartSurfaceToolbarCoordinator {
     private CallbackController mCallbackController = new CallbackController();
 
     StartSurfaceToolbarCoordinator(ViewStub startSurfaceToolbarStub,
-            IdentityDiscController identityDiscController, UserEducationHelper userEducationHelper,
+            UserEducationHelper userEducationHelper,
             OneshotSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier,
-            ThemeColorProvider provider, MenuButtonCoordinator menuButtonCoordinator) {
+            ObservableSupplier<Boolean> identityDiscStateSupplier, ThemeColorProvider provider,
+            MenuButtonCoordinator menuButtonCoordinator,
+            Supplier<ButtonData> identityDiscButtonSupplier) {
         mStub = startSurfaceToolbarStub;
 
         overviewModeBehaviorSupplier.onAvailable(
@@ -78,7 +82,7 @@ public class StartSurfaceToolbarCoordinator {
         // should not be both true.
         assert !(StartSurfaceConfiguration.START_SURFACE_HIDE_INCOGNITO_SWITCH_NO_TAB.getValue()
                 && StartSurfaceConfiguration.START_SURFACE_SHOW_STACK_TAB_SWITCHER.getValue());
-        mToolbarMediator = new StartSurfaceToolbarMediator(mPropertyModel, identityDiscController,
+        mToolbarMediator = new StartSurfaceToolbarMediator(mPropertyModel,
                 (iphCommandBuilder)
                         -> {
                     // TODO(crbug.com/865801): Replace the null check with an assert after fixing or
@@ -90,7 +94,7 @@ public class StartSurfaceToolbarCoordinator {
                 StartSurfaceConfiguration.START_SURFACE_HIDE_INCOGNITO_SWITCH_NO_TAB.getValue(),
                 StartSurfaceConfiguration.START_SURFACE_HIDE_INCOGNITO_SWITCH.getValue(),
                 StartSurfaceConfiguration.START_SURFACE_SHOW_STACK_TAB_SWITCHER.getValue(),
-                menuButtonCoordinator);
+                menuButtonCoordinator, identityDiscStateSupplier, identityDiscButtonSupplier);
 
         mThemeColorProvider = provider;
         mMenuButtonCoordinator = menuButtonCoordinator;

chrome/android/java/src/org/chromium/chrome/browser/toolbar/top/StartSurfaceToolbarMediator.java

@@ -26,11 +26,12 @@ import android.view.View;
 import androidx.annotation.VisibleForTesting;
 
 import org.chromium.base.Callback;
+import org.chromium.base.supplier.ObservableSupplier;
+import org.chromium.base.supplier.Supplier;
 import org.chromium.chrome.browser.compositor.layouts.EmptyOverviewModeObserver;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior.OverviewModeObserver;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeState;
-import org.chromium.chrome.browser.identity_disc.IdentityDiscController;
 import org.chromium.chrome.browser.search_engines.TemplateUrlServiceFactory;
 import org.chromium.chrome.browser.tabmodel.EmptyTabModelSelectorObserver;
 import org.chromium.chrome.browser.tabmodel.TabModel;
@@ -47,11 +48,11 @@ import org.chromium.ui.modelutil.PropertyModel;
 /** The mediator implements interacts between the views and the caller. */
 class StartSurfaceToolbarMediator {
     private final PropertyModel mPropertyModel;
-    private final IdentityDiscController mIdentityDiscController;
     private final Callback<IPHCommandBuilder> mShowIPHCallback;
     private final boolean mHideIncognitoSwitchWhenNoTabs;
     private final boolean mHideIncognitoSwitchOnHomePage;
     private final boolean mShowNewTabAndIdentityDiscAtStart;
+    private final Supplier<ButtonData> mIdentityDiscButtonSupplier;
 
     private TabModelSelector mTabModelSelector;
     private TemplateUrlServiceObserver mTemplateUrlObserver;
@@ -63,19 +64,24 @@ class StartSurfaceToolbarMediator {
     private int mOverviewModeState;
     private boolean mIsGoogleSearchEngine;
 
-    StartSurfaceToolbarMediator(PropertyModel model, IdentityDiscController identityDiscController,
-            Callback<IPHCommandBuilder> showIPHCallback, boolean hideIncognitoSwitchWhenNoTabs,
-            boolean hideIncognitoSwitchOnHomePage, boolean showNewTabAndIdentityDiscAtStart,
-            MenuButtonCoordinator menuButtonCoordinator) {
+    StartSurfaceToolbarMediator(PropertyModel model, Callback<IPHCommandBuilder> showIPHCallback,
+            boolean hideIncognitoSwitchWhenNoTabs, boolean hideIncognitoSwitchOnHomePage,
+            boolean showNewTabAndIdentityDiscAtStart, MenuButtonCoordinator menuButtonCoordinator,
+            ObservableSupplier<Boolean> identityDiscStateSupplier,
+            Supplier<ButtonData> identityDiscButtonSupplier) {
         mPropertyModel = model;
         mOverviewModeState = OverviewModeState.NOT_SHOWN;
-        mIdentityDiscController = identityDiscController;
-        mIdentityDiscController.addObserver(this::identityDiscStateChanged);
         mShowIPHCallback = showIPHCallback;
         mHideIncognitoSwitchWhenNoTabs = hideIncognitoSwitchWhenNoTabs;
         mHideIncognitoSwitchOnHomePage = hideIncognitoSwitchOnHomePage;
         mShowNewTabAndIdentityDiscAtStart = showNewTabAndIdentityDiscAtStart;
         mMenuButtonCoordinator = menuButtonCoordinator;
+        mIdentityDiscButtonSupplier = identityDiscButtonSupplier;
+        identityDiscStateSupplier.addObserver((canShowHint) -> {
+            // If the identity disc wants to be hidden and is hidden, there's nothing we need to do.
+            if (!canShowHint && !mPropertyModel.get(IDENTITY_DISC_IS_VISIBLE)) return;
+            updateIdentityDisc(mIdentityDiscButtonSupplier.get());
+        });
     }
 
     void onNativeLibraryReady() {
@@ -117,14 +123,13 @@ class StartSurfaceToolbarMediator {
                 @Override
                 public void onTabModelSelected(TabModel newModel, TabModel oldModel) {
                     mPropertyModel.set(IS_INCOGNITO, mTabModelSelector.isIncognitoSelected());
-                    updateIdentityDisc(
-                            mIdentityDiscController.getForStartSurface(mOverviewModeState));
+                    updateIdentityDisc(mIdentityDiscButtonSupplier.get());
                     updateIncognitoSwitchVisibility();
                 }
             };
         }
         mPropertyModel.set(IS_INCOGNITO, mTabModelSelector.isIncognitoSelected());
-        updateIdentityDisc(mIdentityDiscController.getForStartSurface(mOverviewModeState));
+        updateIdentityDisc(mIdentityDiscButtonSupplier.get());
         mTabModelSelector.addObserver(mTabModelSelectorObserver);
     }
 
@@ -186,7 +191,7 @@ class StartSurfaceToolbarMediator {
                 updateIncognitoSwitchVisibility();
                 updateNewTabButtonVisibility();
                 updateLogoVisibility(mIsGoogleSearchEngine);
-                updateIdentityDisc(mIdentityDiscController.getForStartSurface(mOverviewModeState));
+                updateIdentityDisc(mIdentityDiscButtonSupplier.get());
             }
             @Override
             public void onOverviewModeStartedShowing(boolean showToolbar) {
@@ -225,14 +230,7 @@ class StartSurfaceToolbarMediator {
         mPropertyModel.set(LOGO_IS_VISIBLE, shouldShowLogo);
     }
 
-    @VisibleForTesting
-    void identityDiscStateChanged(boolean canShowHint) {
-        // If the identity disc wants to be hidden and is hidden, there's nothing we need to do.
-        if (!canShowHint && !mPropertyModel.get(IDENTITY_DISC_IS_VISIBLE)) return;
-        updateIdentityDisc(mIdentityDiscController.getForStartSurface(mOverviewModeState));
-    }
-
-    @VisibleForTesting
+    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
     void updateIdentityDisc(ButtonData buttonData) {
         boolean shouldShow = buttonData.canShow && !mTabModelSelector.isIncognitoSelected();
         if (shouldShow) {
@@ -259,4 +257,10 @@ class StartSurfaceToolbarMediator {
                 || ChromeAccessibilityUtil.get().isAccessibilityEnabled();
         mPropertyModel.set(NEW_TAB_BUTTON_IS_VISIBLE, isShownTabswitcherState);
     }
+
+    @VisibleForTesting
+    @OverviewModeState
+    int getOverviewModeStateForTesting() {
+        return mOverviewModeState;
+    }
 }

chrome/android/java/src/org/chromium/chrome/browser/toolbar/top/ToolbarLayout.java

@@ -17,20 +17,20 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.FrameLayout;
 import android.widget.ProgressBar;
+
 import androidx.annotation.CallSuper;
 import androidx.annotation.ColorRes;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
+
+import org.chromium.base.Callback;
 import org.chromium.base.ObserverList;
 import org.chromium.base.TraceEvent;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ThemeColorProvider;
 import org.chromium.chrome.browser.ThemeColorProvider.ThemeColorObserver;
 import org.chromium.chrome.browser.ThemeColorProvider.TintObserver;
-import org.chromium.chrome.browser.compositor.Invalidator;
-import org.chromium.chrome.browser.compositor.layouts.LayoutUpdateHost;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
-import org.chromium.chrome.browser.findinpage.FindToolbar;
 import org.chromium.chrome.browser.ntp.NewTabPage;
 import org.chromium.chrome.browser.omnibox.LocationBar;
 import org.chromium.chrome.browser.omnibox.UrlBarData;
@@ -58,7 +58,7 @@ import org.chromium.ui.base.ViewUtils;
  */
 public abstract class ToolbarLayout
         extends FrameLayout implements TintObserver, ThemeColorObserver {
-    private Invalidator mInvalidator;
+    private Callback<Runnable> mInvalidator;
 
     protected final ObserverList<UrlExpansionObserver> mUrlExpansionObservers =
             new ObserverList<>();
@@ -411,7 +411,7 @@ public abstract class ToolbarLayout
      * {@link Invalidator} a chance to defer the actual invalidate to sync drawing.
      * @param invalidator An {@link Invalidator} instance.
      */
-    void setPaintInvalidator(Invalidator invalidator) {
+    void setInvalidatorCallback(Callback<Runnable> invalidator) {
         mInvalidator = invalidator;
     }
 
@@ -420,12 +420,8 @@ public abstract class ToolbarLayout
      * {@link #setPaintInvalidator(Invalidator)} to decide when to actually invalidate.
      * @param client A {@link Invalidator.Client} instance that wants to be invalidated.
      */
-    void triggerPaintInvalidate(Invalidator.Client client) {
-        if (mInvalidator == null) {
-            client.doInvalidate();
-        } else {
-            mInvalidator.invalidate(client);
-        }
+    protected void triggerPaintInvalidate(Runnable clientInvalidator) {
+        mInvalidator.onResult(clientInvalidator);
     }
 
     /**
@@ -603,7 +599,7 @@ public abstract class ToolbarLayout
         return false;
     }
 
-    void setLayoutUpdateHost(LayoutUpdateHost layoutUpdateHost) {}
+    void setLayoutUpdater(Runnable layoutUpdater) {}
 
     void setOverviewModeBehavior(OverviewModeBehavior overviewModeBehavior) {}
 

chrome/android/java/src/org/chromium/chrome/browser/toolbar/top/ToolbarPhone.java

@@ -49,8 +49,6 @@ import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.MathUtils;
 import org.chromium.base.TraceEvent;
 import org.chromium.chrome.R;
-import org.chromium.chrome.browser.compositor.Invalidator;
-import org.chromium.chrome.browser.compositor.layouts.LayoutUpdateHost;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.device.DeviceClassManager;
 import org.chromium.chrome.browser.feature_engagement.TrackerFactory;
@@ -90,9 +88,8 @@ import java.util.List;
 /**
  * Phone specific toolbar implementation.
  */
-public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, OnClickListener,
-                                                           NewTabPage.OnSearchBoxScrollListener,
-                                                           TabCountObserver {
+public class ToolbarPhone extends ToolbarLayout
+        implements OnClickListener, NewTabPage.OnSearchBoxScrollListener, TabCountObserver {
     /** The amount of time transitioning from one theme color to another should take in ms. */
     public static final long THEME_COLOR_TRANSITION_DURATION = 250;
 
@@ -240,7 +237,7 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
 
     private boolean mIsHomeButtonEnabled;
 
-    private LayoutUpdateHost mLayoutUpdateHost;
+    private Runnable mLayoutUpdater;
 
     /** The vertical inset of the location bar background. */
     private int mLocationBarBackgroundVerticalInset;
@@ -311,7 +308,7 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
                 @Override
                 public void set(ToolbarPhone object, Float value) {
                     object.mTabSwitcherModePercent = value;
-                    triggerPaintInvalidate(ToolbarPhone.this);
+                    triggerPaintInvalidate(ToolbarPhone.this::postInvalidateOnAnimation);
                 }
             };
 
@@ -1322,11 +1319,6 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
         canvas.restore();
     }
 
-    @Override
-    public void doInvalidate() {
-        postInvalidateOnAnimation();
-    }
-
     /**
      * Translates the canvas to ensure the specified view's coordinates are at 0, 0.
      *
@@ -1576,8 +1568,8 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
     }
 
     @Override
-    public void setLayoutUpdateHost(LayoutUpdateHost layoutUpdateHost) {
-        mLayoutUpdateHost = layoutUpdateHost;
+    public void setLayoutUpdater(Runnable layoutUpdater) {
+        mLayoutUpdater = layoutUpdater;
     }
 
     @Override
@@ -1654,7 +1646,7 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
         // TODO(amaralp): Have the LocationBar listen to tint changes.
         if (mLocationBar != null) mLocationBar.updateVisualsForState();
 
-        if (mLayoutUpdateHost != null) mLayoutUpdateHost.requestUpdate();
+        if (mLayoutUpdater != null) mLayoutUpdater.run();
     }
 
     @Override
@@ -1730,7 +1722,7 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
         // Request a texture update to ensure a texture is captured before the user
         // re-enters the tab switcher.
         postInvalidate();
-        mLayoutUpdateHost.requestUpdate();
+        mLayoutUpdater.run();
     }
 
     @Override
@@ -2294,7 +2286,7 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
         });
         mBrandColorTransitionAnimation.start();
         mBrandColorTransitionActive = true;
-        if (mLayoutUpdateHost != null) mLayoutUpdateHost.requestUpdate();
+        if (mLayoutUpdater != null) mLayoutUpdater.run();
     }
 
     private void updateNtpAnimationState() {
@@ -2462,8 +2454,8 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
 
         // Refresh the toolbar texture.
         if ((mVisualState == VisualState.BRAND_COLOR || visualStateChanged)
-                && mLayoutUpdateHost != null) {
-            mLayoutUpdateHost.requestUpdate();
+                && mLayoutUpdater != null) {
+            mLayoutUpdater.run();
         }
         updateShadowVisibility();
         updateUrlExpansionAnimation();
@@ -2602,7 +2594,7 @@ public class ToolbarPhone extends ToolbarLayout implements Invalidator.Client, O
     }
 
     private void requestLayoutHostUpdateForOptionalButton() {
-        if (mLayoutUpdateHost != null) mLayoutUpdateHost.requestUpdate();
+        if (mLayoutUpdater != null) mLayoutUpdater.run();
         getViewTreeObserver().removeOnGlobalLayoutListener(mOptionalButtonLayoutListener);
     }
 

chrome/android/java/src/org/chromium/chrome/browser/toolbar/top/TopToolbarCoordinator.java

@@ -4,7 +4,6 @@
 
 package org.chromium.chrome.browser.toolbar.top;
 
-import android.content.Context;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.view.View;
@@ -14,20 +13,18 @@ import android.view.View.OnLongClickListener;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 
+import org.chromium.base.Callback;
 import org.chromium.base.CallbackController;
 import org.chromium.base.supplier.ObservableSupplier;
 import org.chromium.base.supplier.OneShotCallback;
 import org.chromium.base.supplier.OneshotSupplier;
+import org.chromium.base.supplier.Supplier;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ThemeColorProvider;
-import org.chromium.chrome.browser.compositor.Invalidator;
-import org.chromium.chrome.browser.compositor.layouts.LayoutManager;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
-import org.chromium.chrome.browser.findinpage.FindToolbar;
-import org.chromium.chrome.browser.homepage.HomepageManager;
-import org.chromium.chrome.browser.identity_disc.IdentityDiscController;
 import org.chromium.chrome.browser.omnibox.LocationBar;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
+import org.chromium.chrome.browser.toolbar.ButtonData;
 import org.chromium.chrome.browser.toolbar.ButtonDataProvider;
 import org.chromium.chrome.browser.toolbar.IncognitoStateProvider;
 import org.chromium.chrome.browser.toolbar.TabCountProvider;
@@ -75,7 +72,6 @@ public class TopToolbarCoordinator implements Toolbar {
      */
     private @Nullable StartSurfaceToolbarCoordinator mStartSurfaceToolbarCoordinator;
 
-    private final IdentityDiscController mIdentityDiscController;
     private OptionalBrowsingModeButtonController mOptionalButtonController;
 
     private MenuButtonCoordinator mMenuButtonCoordinator;
@@ -83,19 +79,10 @@ public class TopToolbarCoordinator implements Toolbar {
     private CallbackController mCallbackController = new CallbackController();
     private ObservableSupplier<TabModelSelector> mTabModelSelectorSupplier;
 
-    private HomepageManager.HomepageStateListener mHomepageStateListener =
-            new HomepageManager.HomepageStateListener() {
-                @Override
-                public void onHomepageStateUpdated() {
-                    mToolbarLayout.onHomeButtonUpdate(HomepageManager.isHomepageEnabled());
-                }
-            };
-
     /**
      * Creates a new {@link TopToolbarCoordinator}.
      * @param controlContainer The {@link ToolbarControlContainer} for the containing activity.
      * @param toolbarLayout The {@link ToolbarLayout}.
-     * @param identityDiscController Class that controls the state of the identity disc.
      * @param userEducationHelper Helper class for showing in-product help text bubbles.
      * @param buttonDataProviders List of classes that wish to display an optional button in the
      *         browsing mode toolbar.
@@ -104,20 +91,29 @@ public class TopToolbarCoordinator implements Toolbar {
      * @param normalThemeColorProvider The {@link ThemeColorProvider} for normal mode.
      * @param overviewThemeColorProvider The {@link ThemeColorProvider} for overview mode.
      * @param tabModelSelectorSupplier Supplier of the {@link TabModelSelector}.
+     * @param homeButtonVisibilitySupplier Supplier of the visibility change of Home button.
+     * @param identityDiscStateSupplier Supplier of the state change of identity disc button.
+     * @param invalidatorCallback Callback that will be invoked  when the toolbar attempts to
+     *        invalidate the drawing surface.  This will give the object that registers as the host
+     *        for the {@link Invalidator} a chance to defer the actual invalidate to sync drawing.
+     * @param identityDiscButtonSupplier Supplier of Identity Disc button.
      */
     public TopToolbarCoordinator(ToolbarControlContainer controlContainer,
-            ToolbarLayout toolbarLayout, IdentityDiscController identityDiscController,
-            ToolbarDataProvider toolbarDataProvider, ToolbarTabController tabController,
-            UserEducationHelper userEducationHelper, List<ButtonDataProvider> buttonDataProviders,
+            ToolbarLayout toolbarLayout, ToolbarDataProvider toolbarDataProvider,
+            ToolbarTabController tabController, UserEducationHelper userEducationHelper,
+            List<ButtonDataProvider> buttonDataProviders,
             OneshotSupplier<OverviewModeBehavior> overviewModeBehaviorSupplier,
             ThemeColorProvider normalThemeColorProvider,
             ThemeColorProvider overviewThemeColorProvider,
             MenuButtonCoordinator browsingModeMenuButtonCoordinator,
             MenuButtonCoordinator startSurfaceMenuButtonCoordinator,
-            ObservableSupplier<AppMenuButtonHelper> appMenuButtonHelperSupplier, Context context,
-            ObservableSupplier<TabModelSelector> tabModelSelectorSupplier) {
+            ObservableSupplier<AppMenuButtonHelper> appMenuButtonHelperSupplier,
+            ObservableSupplier<TabModelSelector> tabModelSelectorSupplier,
+            ObservableSupplier<Boolean> homeButtonVisibilitySupplier,
+            ObservableSupplier<Boolean> identityDiscStateSupplier,
+            Callback<Runnable> invalidatorCallback,
+            Supplier<ButtonData> identityDiscButtonSupplier) {
         mToolbarLayout = toolbarLayout;
-        mIdentityDiscController = identityDiscController;
         mMenuButtonCoordinator = browsingModeMenuButtonCoordinator;
         mOptionalButtonController = new OptionalBrowsingModeButtonController(buttonDataProviders,
                 userEducationHelper, mToolbarLayout, () -> toolbarDataProvider.getTab());
@@ -131,8 +127,9 @@ public class TopToolbarCoordinator implements Toolbar {
             if (StartSurfaceConfiguration.isStartSurfaceEnabled()) {
                 mStartSurfaceToolbarCoordinator = new StartSurfaceToolbarCoordinator(
                         controlContainer.getRootView().findViewById(R.id.tab_switcher_toolbar_stub),
-                        mIdentityDiscController, userEducationHelper, overviewModeBehaviorSupplier,
-                        overviewThemeColorProvider, startSurfaceMenuButtonCoordinator);
+                        userEducationHelper, overviewModeBehaviorSupplier,
+                        identityDiscStateSupplier, overviewThemeColorProvider,
+                        startSurfaceMenuButtonCoordinator, identityDiscButtonSupplier);
             } else {
                 mTabSwitcherModeCoordinatorPhone = new TabSwitcherModeTTCoordinatorPhone(
                         controlContainer.getRootView().findViewById(
@@ -140,12 +137,13 @@ public class TopToolbarCoordinator implements Toolbar {
             }
         }
         controlContainer.setToolbar(this);
-        HomepageManager.getInstance().addListener(mHomepageStateListener);
         mToolbarLayout.initialize(toolbarDataProvider, tabController, mMenuButtonCoordinator);
 
         mToolbarLayout.setThemeColorProvider(normalThemeColorProvider);
         mAppMenuButtonHelperSupplier = appMenuButtonHelperSupplier;
         new OneShotCallback<>(mAppMenuButtonHelperSupplier, this::setAppMenuButtonHelper);
+        homeButtonVisibilitySupplier.addObserver((show) -> mToolbarLayout.onHomeButtonUpdate(show));
+        mToolbarLayout.setInvalidatorCallback(invalidatorCallback);
     }
 
     /**
@@ -163,14 +161,14 @@ public class TopToolbarCoordinator implements Toolbar {
      * <p>
      * Calling this must occur after the native library have completely loaded.
      *
-     * @param layoutManager A {@link LayoutManager} instance used to watch for scene changes.
+     * @param layoutUpdater A {@link Runnable} used to request layout update upon scene change.
      * @param tabSwitcherClickHandler The click handler for the tab switcher button.
      * @param tabSwitcherLongClickHandler The long click handler for the tab switcher button.
      * @param newTabClickHandler The click handler for the new tab button.
      * @param bookmarkClickHandler The click handler for the bookmarks button.
      * @param customTabsBackClickHandler The click handler for the custom tabs back button.
      */
-    public void initializeWithNative(LayoutManager layoutManager,
+    public void initializeWithNative(Runnable layoutUpdater,
             OnClickListener tabSwitcherClickHandler,
             OnLongClickListener tabSwitcherLongClickHandler, OnClickListener newTabClickHandler,
             OnClickListener bookmarkClickHandler, OnClickListener customTabsBackClickHandler) {
@@ -195,7 +193,7 @@ public class TopToolbarCoordinator implements Toolbar {
         mToolbarLayout.setOnTabSwitcherLongClickHandler(tabSwitcherLongClickHandler);
         mToolbarLayout.setBookmarkClickHandler(bookmarkClickHandler);
         mToolbarLayout.setCustomTabCloseClickHandler(customTabsBackClickHandler);
-        mToolbarLayout.setLayoutUpdateHost(layoutManager);
+        mToolbarLayout.setLayoutUpdater(layoutUpdater);
 
         mToolbarLayout.onNativeLibraryReady();
     }
@@ -230,7 +228,6 @@ public class TopToolbarCoordinator implements Toolbar {
      * Cleans up any code as necessary.
      */
     public void destroy() {
-        HomepageManager.getInstance().removeListener(mHomepageStateListener);
         mToolbarLayout.destroy();
         if (mTabSwitcherModeCoordinatorPhone != null) {
             mTabSwitcherModeCoordinatorPhone.destroy();
@@ -302,8 +299,8 @@ public class TopToolbarCoordinator implements Toolbar {
      * {@link Invalidator} a chance to defer the actual invalidate to sync drawing.
      * @param invalidator An {@link Invalidator} instance.
      */
-    public void setPaintInvalidator(Invalidator invalidator) {
-        mToolbarLayout.setPaintInvalidator(invalidator);
+    public void setInvalidatorCallback(Callback<Runnable> callback) {
+        mToolbarLayout.setInvalidatorCallback(callback);
     }
 
     /**

chrome/android/junit/src/org/chromium/chrome/browser/toolbar/top/StartSurfaceToolbarMediatorUnitTest.java

@@ -41,6 +41,7 @@ import org.mockito.MockitoAnnotations;
 import org.robolectric.annotation.Config;
 
 import org.chromium.base.Callback;
+import org.chromium.base.supplier.ObservableSupplierImpl;
 import org.chromium.base.test.BaseRobolectricTestRunner;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior.OverviewModeObserver;
@@ -99,6 +100,7 @@ public class StartSurfaceToolbarMediatorUnitTest {
 
     private ButtonData mButtonData;
     private ButtonData mDisabledButtonData;
+    private ObservableSupplierImpl<Boolean> mIdentityDiscStateSupplier;
 
     @Before
     public void setUp() {
@@ -113,6 +115,7 @@ public class StartSurfaceToolbarMediatorUnitTest {
                         .build();
         mButtonData = new ButtonData(false, mDrawable, mOnClickListener, 0, false, null, true);
         mDisabledButtonData = new ButtonData(false, null, null, 0, false, null, true);
+        mIdentityDiscStateSupplier = new ObservableSupplierImpl<>();
         doReturn(mButtonData)
                 .when(mIdentityDiscController)
                 .getForStartSurface(OverviewModeState.SHOWN_HOMEPAGE);
@@ -589,17 +592,17 @@ public class StartSurfaceToolbarMediatorUnitTest {
         assertEquals(mPropertyModel.get(IDENTITY_DISC_IS_VISIBLE), false);
 
         mButtonData.canShow = true;
-        mMediator.identityDiscStateChanged(true);
+        mIdentityDiscStateSupplier.set(true);
         assertEquals(mPropertyModel.get(IDENTITY_DISC_IS_VISIBLE), true);
 
         mButtonData.canShow = false;
-        mMediator.identityDiscStateChanged(false);
+        mIdentityDiscStateSupplier.set(false);
         assertEquals(mPropertyModel.get(IDENTITY_DISC_IS_VISIBLE), false);
 
         // updateIdentityDisc() should properly handle a hint that contradicts the true value of
         // canShow.
         mButtonData.canShow = false;
-        mMediator.identityDiscStateChanged(true);
+        mIdentityDiscStateSupplier.set(true);
         assertEquals(mPropertyModel.get(IDENTITY_DISC_IS_VISIBLE), false);
     }
 
@@ -720,9 +723,12 @@ public class StartSurfaceToolbarMediatorUnitTest {
 
     private void createMediator(boolean hideIncognitoSwitchWhenNoTabs,
             boolean hideIncognitoSwitchOnHomePage, boolean showNewTabAndIdentityDiscAtStart) {
-        mMediator = new StartSurfaceToolbarMediator(mPropertyModel, mIdentityDiscController,
-                mMockCallback, hideIncognitoSwitchWhenNoTabs, hideIncognitoSwitchOnHomePage,
-                showNewTabAndIdentityDiscAtStart, mMenuButtonCoordinator);
+        mMediator = new StartSurfaceToolbarMediator(mPropertyModel, mMockCallback,
+                hideIncognitoSwitchWhenNoTabs, hideIncognitoSwitchOnHomePage,
+                showNewTabAndIdentityDiscAtStart, mMenuButtonCoordinator,
+                mIdentityDiscStateSupplier,
+                () -> mIdentityDiscController.getForStartSurface(
+                        mMediator.getOverviewModeStateForTesting()));
         mMediator.setOverviewModeBehavior(mOverviewModeBehavior);
         verify(mOverviewModeBehavior)
                 .addOverviewModeObserver(mOverviewModeObserverCaptor.capture());