Revert "Make LayoutManager observer notification async"

This reverts commit 9183c032.

Reason for revert: 
https://ci.chromium.org/p/chromium/builders/ci/Lollipop%20Phone%20Tester

Original change's description:
> Make LayoutManager observer notification async
> 
> The process of supplying OverviewModeBehavior is now async to prevent re-entrancy in OneshotSupplier (as of https://crrev.com/c/2321067). Since observer notification in LayoutManager is synchronous, this creates a race condition where observers miss an update because an event (e.g. a touch event, as in the linked bug) queued before the call to set() can trigger synchronous observer notification before observers can add themselves.
> 
> Bug: 1129783
> Change-Id: Ia482a109576539d54f171950468e490972e72bc1
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2418981
> Reviewed-by: David Trainor <dtrainor@chromium.org>
> Reviewed-by: Xi Han <hanxi@chromium.org>
> Commit-Queue: Patrick Noland <pnoland@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#809386}

TBR=dtrainor@chromium.org,hanxi@chromium.org,pnoland@chromium.org

Change-Id: Ic1028b99d727da8bf2b85955745068de1eaa45bd
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1129783
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2426724Reviewed-by: Gang Wu <gangwu@chromium.org>
Commit-Queue: Gang Wu <gangwu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809787}

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

@@ -561,8 +561,9 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
                 }
             }
             mLayoutManager = new LayoutManagerChromePhone(compositorViewHolder, mContentContainer,
-                    mStartSurface, getTabContentManagerSupplier(), mOverviewModeBehaviorSupplier);
+                    mStartSurface, getTabContentManagerSupplier());
             mOverviewModeController = mLayoutManager;
+            mOverviewModeBehaviorSupplier.set(mOverviewModeController);
         }
     }
 
@@ -571,10 +572,10 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
 
         try (TraceEvent e = TraceEvent.scoped(
                      "ChromeTabbedActivity.setupCompositorContentPreNativeForTablet")) {
-            mLayoutManager =
-                    new LayoutManagerChromeTablet(getCompositorViewHolder(), mContentContainer,
-                            getTabContentManagerSupplier(), mOverviewModeBehaviorSupplier);
+            mLayoutManager = new LayoutManagerChromeTablet(
+                    getCompositorViewHolder(), mContentContainer, getTabContentManagerSupplier());
             mOverviewModeController = mLayoutManager;
+            mOverviewModeBehaviorSupplier.set(mOverviewModeController);
         }
     }
 
@@ -838,7 +839,7 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
         if (!mPendingInitialTabCreation
                 && !(TabUiFeatureUtilities.supportInstantStart(isTablet())
                         && shouldShowTabSwitcherOnStart())) {
-            setInitialOverviewState();
+            setInitialOverviewStateAsync();
         }
 
         if (TabUiFeatureUtilities.isConditionalTabStripEnabled()
@@ -915,7 +916,14 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
         }
     }
 
-    private void setInitialOverviewState() {
+    // Posts a call to setInitialOverviewStateSync that will trigger after observers of
+    // mOverviewModeBehaviorSupplier have a chance to process the supplied OverviewModeBehavior and
+    // add themselves as observers.
+    private void setInitialOverviewStateAsync() {
+        mOverviewModeBehaviorSupplier.onAvailable((unused) -> setInitalOverviewStateSync());
+    }
+
+    private void setInitalOverviewStateSync() {
         boolean isOverviewVisible = mOverviewModeController.overviewVisible();
 
         if (shouldShowTabSwitcherOnStart() && !isOverviewVisible) {
@@ -1127,7 +1135,7 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
         if (hasStartWithNativeBeenCalled()
                 && !(TabUiFeatureUtilities.supportInstantStart(isTablet())
                         && shouldShowTabSwitcherOnStart())) {
-            setInitialOverviewState();
+            setInitialOverviewStateAsync();
         }
     }
 
@@ -1512,7 +1520,7 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
             if (shouldShowTabSwitcherOnStart()) {
                 mLayoutManager.setTabModelSelector(mTabModelSelectorImpl);
                 mIsAccessibilityTabSwitcherEnabled = DeviceClassManager.enableAccessibilityLayout();
-                setInitialOverviewState();
+                setInitialOverviewStateAsync();
             }
         }
     }

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

@@ -14,7 +14,6 @@ import org.chromium.base.Callback;
 import org.chromium.base.ObserverList;
 import org.chromium.base.metrics.RecordUserAction;
 import org.chromium.base.supplier.ObservableSupplier;
-import org.chromium.base.supplier.OneshotSupplierImpl;
 import org.chromium.chrome.browser.ActivityTabProvider;
 import org.chromium.chrome.browser.accessibility_tab_switcher.OverviewListLayout;
 import org.chromium.chrome.browser.browser_controls.BrowserControlsStateProvider;
@@ -77,7 +76,6 @@ public class LayoutManagerChrome
     private boolean mCreateOverviewLayout;
 
     protected ObservableSupplier<TabContentManager> mTabContentManagerSupplier;
-    private final OneshotSupplierImpl<OverviewModeBehavior> mOverviewModeBehaviorSupplier;
 
     /**
      * Creates the {@link LayoutManagerChrome} instance.
@@ -89,8 +87,7 @@ public class LayoutManagerChrome
      */
     public LayoutManagerChrome(LayoutManagerHost host, ViewGroup contentContainer,
             boolean createOverviewLayout, @Nullable StartSurface startSurface,
-            ObservableSupplier<TabContentManager> tabContentManagerSupplier,
-            OneshotSupplierImpl<OverviewModeBehavior> overviewModeBehaviorSupplier) {
+            ObservableSupplier<TabContentManager> tabContentManagerSupplier) {
         super(host, contentContainer, tabContentManagerSupplier);
         Context context = host.getContext();
         LayoutRenderHost renderHost = host.getLayoutRenderHost();
@@ -122,8 +119,10 @@ public class LayoutManagerChrome
                     @Override
                     public void onStateChanged(@OverviewModeState int overviewModeState,
                             boolean shouldShowTabSwitcherToolbar) {
-                        notifyObserversStateChanged(
-                                overviewModeState, shouldShowTabSwitcherToolbar);
+                        for (OverviewModeObserver observer : mOverviewModeObservers) {
+                            observer.onOverviewModeStateChanged(
+                                    overviewModeState, shouldShowTabSwitcherToolbar);
+                        }
                     }
                 });
                 final ObservableSupplier<? extends BrowserControlsStateProvider>
@@ -135,9 +134,6 @@ public class LayoutManagerChrome
                 mCreateOverviewLayout = true;
             }
         }
-
-        mOverviewModeBehaviorSupplier = overviewModeBehaviorSupplier;
-        mOverviewModeBehaviorSupplier.set(this);
     }
 
     /**
@@ -282,7 +278,9 @@ public class LayoutManagerChrome
         if (isOverviewLayout(layoutBeingShown)) {
             boolean showToolbar = animate && (!mEnableAnimations
                     || getTabModelSelector().getCurrentModel().getCount() <= 0);
-            notifyObserversStartedShowing(showToolbar);
+            for (OverviewModeObserver observer : mOverviewModeObservers) {
+                observer.onOverviewModeStartedShowing(showToolbar);
+            }
         }
     }
 
@@ -300,7 +298,9 @@ public class LayoutManagerChrome
 
             boolean creatingNtp = layoutBeingHidden == mOverviewLayout && mCreatingNtp;
 
-            notifyObserversStartedHiding(showToolbar, creatingNtp);
+            for (OverviewModeObserver observer : mOverviewModeObservers) {
+                observer.onOverviewModeStartedHiding(showToolbar, creatingNtp);
+            }
         }
     }
 
@@ -309,7 +309,9 @@ public class LayoutManagerChrome
         super.doneShowing();
 
         if (isOverviewLayout(getActiveLayout())) {
-            notifyObserversFinishedShowing();
+            for (OverviewModeObserver observer : mOverviewModeObservers) {
+                observer.onOverviewModeFinishedShowing();
+            }
         }
     }
 
@@ -325,7 +327,9 @@ public class LayoutManagerChrome
         super.doneHiding();
 
         if (isOverviewLayout(layoutBeingHidden)) {
-            notifyObserversFinishedHiding();
+            for (OverviewModeObserver observer : mOverviewModeObservers) {
+                observer.onOverviewModeFinishedHiding();
+            }
         }
     }
 
@@ -592,46 +596,4 @@ public class LayoutManagerChrome
                     .closeTab(lastTab, tab, false, false, false);
         }
     }
-
-    private void notifyObserversStartedShowing(boolean showToolbar) {
-        mOverviewModeBehaviorSupplier.onAvailable((unused) -> {
-            for (OverviewModeObserver overviewModeObserver : mOverviewModeObservers) {
-                overviewModeObserver.onOverviewModeStartedShowing(showToolbar);
-            }
-        });
-    }
-
-    private void notifyObserversFinishedShowing() {
-        mOverviewModeBehaviorSupplier.onAvailable((unused) -> {
-            for (OverviewModeObserver overviewModeObserver : mOverviewModeObservers) {
-                overviewModeObserver.onOverviewModeFinishedShowing();
-            }
-        });
-    }
-
-    private void notifyObserversStartedHiding(boolean showToolbar, boolean creatingNtp) {
-        mOverviewModeBehaviorSupplier.onAvailable((unused) -> {
-            for (OverviewModeObserver overviewModeObserver : mOverviewModeObservers) {
-                overviewModeObserver.onOverviewModeStartedHiding(showToolbar, creatingNtp);
-            }
-        });
-    }
-
-    private void notifyObserversFinishedHiding() {
-        mOverviewModeBehaviorSupplier.onAvailable((unused) -> {
-            for (OverviewModeObserver overviewModeObserver : mOverviewModeObservers) {
-                overviewModeObserver.onOverviewModeFinishedHiding();
-            }
-        });
-    }
-
-    private void notifyObserversStateChanged(
-            @OverviewModeState int overviewModeState, boolean shouldShowTabSwitcherToolbar) {
-        mOverviewModeBehaviorSupplier.onAvailable((unused) -> {
-            for (OverviewModeObserver overviewModeObserver : mOverviewModeObservers) {
-                overviewModeObserver.onOverviewModeStateChanged(
-                        overviewModeState, shouldShowTabSwitcherToolbar);
-            }
-        });
-    }
 }

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

@@ -8,7 +8,6 @@ import android.content.Context;
 import android.view.ViewGroup;
 
 import org.chromium.base.supplier.ObservableSupplier;
-import org.chromium.base.supplier.OneshotSupplierImpl;
 import org.chromium.chrome.browser.ActivityTabProvider;
 import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
 import org.chromium.chrome.browser.compositor.layouts.phone.SimpleAnimationLayout;
@@ -42,10 +41,8 @@ public class LayoutManagerChromePhone extends LayoutManagerChrome {
      */
     public LayoutManagerChromePhone(LayoutManagerHost host, ViewGroup contentContainer,
             StartSurface startSurface,
-            ObservableSupplier<TabContentManager> tabContentManagerSupplier,
-            OneshotSupplierImpl<OverviewModeBehavior> overviewModeBehaviorSupplier) {
-        super(host, contentContainer, true, startSurface, tabContentManagerSupplier,
-                overviewModeBehaviorSupplier);
+            ObservableSupplier<TabContentManager> tabContentManagerSupplier) {
+        super(host, contentContainer, true, startSurface, tabContentManagerSupplier);
     }
 
     @Override

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

@@ -7,7 +7,6 @@ package org.chromium.chrome.browser.compositor.layouts;
 import android.view.ViewGroup;
 
 import org.chromium.base.supplier.ObservableSupplier;
-import org.chromium.base.supplier.OneshotSupplierImpl;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ActivityTabProvider;
 import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
@@ -38,10 +37,8 @@ public class LayoutManagerChromeTablet extends LayoutManagerChrome {
      * @param tabContentManagerSupplier Supplier of the {@link TabContentManager} instance.
      */
     public LayoutManagerChromeTablet(LayoutManagerHost host, ViewGroup contentContainer,
-            ObservableSupplier<TabContentManager> tabContentManagerSupplier,
-            OneshotSupplierImpl<OverviewModeBehavior> overviewModeBehaviorSupplier) {
-        super(host, contentContainer, false, null, tabContentManagerSupplier,
-                overviewModeBehaviorSupplier);
+            ObservableSupplier<TabContentManager> tabContentManagerSupplier) {
+        super(host, contentContainer, false, null, tabContentManagerSupplier);
 
         mTabStripLayoutHelperManager = new StripLayoutHelperManager(
                 host.getContext(), this, mHost.getLayoutRenderHost(), () -> mTitleCache);

chrome/android/javatests/src/org/chromium/chrome/browser/app/appmenu/TabbedAppMenuTest.java

@@ -237,8 +237,7 @@ public class TabbedAppMenuTest {
                 () -> mActivityTestRule.getActivity().getLayoutManager().hideOverview(false));
         Assert.assertFalse("Overview shouldn't be showing.",
                 mActivityTestRule.getActivity().getOverviewModeBehavior().overviewVisible());
-        CriteriaHelper.pollUiThread(
-                () -> !mAppMenuHandler.isAppMenuShowing(), "App menu shouldn't be showing.");
+        Assert.assertFalse("App menu shouldn't be showing.", mAppMenuHandler.isAppMenuShowing());
     }
 
     @Test

chrome/android/javatests/src/org/chromium/chrome/browser/compositor/layouts/LayoutManagerTest.java

@@ -30,7 +30,6 @@ import org.mockito.MockitoAnnotations;
 
 import org.chromium.base.MathUtils;
 import org.chromium.base.supplier.ObservableSupplierImpl;
-import org.chromium.base.supplier.OneshotSupplierImpl;
 import org.chromium.base.test.UiThreadTest;
 import org.chromium.base.test.util.CommandLineFlags;
 import org.chromium.base.test.util.DisabledTest;
@@ -167,10 +166,8 @@ public class LayoutManagerTest implements MockTabModelDelegate {
 
         ObservableSupplierImpl<TabContentManager> tabContentManagerSupplier =
                 new ObservableSupplierImpl<>();
-        OneshotSupplierImpl<OverviewModeBehavior> overviewModeBehaviorSupplier =
-                new OneshotSupplierImpl<>();
-        mManagerPhone = new LayoutManagerChromePhone(layoutManagerHost, container, null,
-                tabContentManagerSupplier, overviewModeBehaviorSupplier);
+        mManagerPhone = new LayoutManagerChromePhone(
+                layoutManagerHost, container, null, tabContentManagerSupplier);
         tabContentManagerSupplier.set(tabContentManager);
         mManager = mManagerPhone;
         CompositorAnimationHandler.setTestingMode(true);

chrome/android/javatests/src/org/chromium/chrome/browser/ui/system/StatusBarColorControllerTest.java

@@ -4,7 +4,6 @@
 
 package org.chromium.chrome.browser.ui.system;
 
-import android.app.Activity;
 import android.content.res.Resources;
 import android.graphics.Color;
 import android.os.Build;
@@ -12,7 +11,6 @@ import android.os.Build;
 import androidx.annotation.ColorInt;
 import androidx.test.filters.LargeTest;
 
-import org.hamcrest.Matchers;
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Rule;
@@ -36,15 +34,10 @@ import org.chromium.chrome.test.ChromeTabbedActivityTestRule;
 import org.chromium.chrome.test.util.browser.Features;
 import org.chromium.chrome.test.util.browser.ThemeTestUtils;
 import org.chromium.components.browser_ui.styles.ChromeColors;
-import org.chromium.content_public.browser.test.util.Criteria;
-import org.chromium.content_public.browser.test.util.CriteriaHelper;
 import org.chromium.content_public.browser.test.util.TestThreadUtils;
 import org.chromium.ui.test.util.UiRestriction;
 import org.chromium.ui.util.ColorUtils;
 
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.TimeoutException;
-
 /**
  * {@link StatusBarColorController} tests.
  * There are additional status bar color tests in {@link BrandColorTest}.
@@ -75,7 +68,7 @@ public class StatusBarColorControllerTest {
     @Feature({"StatusBar"})
     @MinAndroidSdkLevel(Build.VERSION_CODES.LOLLIPOP_MR1)
     @Restriction({UiRestriction.RESTRICTION_TYPE_PHONE}) // Status bar is always black on tablets
-    public void testColorToggleIncongitoInOverview() throws Exception {
+    public void testColorToggleIncongitoInOverview() {
         ChromeTabbedActivity activity = mActivityTestRule.getActivity();
         Resources resources = activity.getResources();
         final int expectedOverviewStandardColor = defaultColorFallbackToBlack(
@@ -91,7 +84,8 @@ public class StatusBarColorControllerTest {
         TestThreadUtils.runOnUiThreadBlocking(
                 () -> { activity.getLayoutManager().showOverview(false /* animate */); });
 
-        waitForStatusBarColor(activity, expectedOverviewIncognitoColor);
+        ThemeTestUtils.assertStatusBarColor(activity, expectedOverviewIncognitoColor);
+
         TestThreadUtils.runOnUiThreadBlocking(
                 () -> { tabModelSelector.selectModel(false /* incongito */); });
         ThemeTestUtils.assertStatusBarColor(activity, expectedOverviewStandardColor);
@@ -115,11 +109,11 @@ public class StatusBarColorControllerTest {
                 "/chrome/test/data/android/theme_color_test.html");
         mActivityTestRule.loadUrl(pageWithBrandColorUrl);
         ThemeTestUtils.waitForThemeColor(activity, Color.RED);
-        waitForStatusBarColor(activity, Color.RED);
+        ThemeTestUtils.assertStatusBarColor(activity, Color.RED);
 
         TestThreadUtils.runOnUiThreadBlocking(
                 () -> { activity.getLayoutManager().showOverview(false /* animate */); });
-        waitForStatusBarColor(activity, expectedDefaultStandardColor);
+        ThemeTestUtils.assertStatusBarColor(activity, expectedDefaultStandardColor);
     }
 
     /**
@@ -197,12 +191,4 @@ public class StatusBarColorControllerTest {
         final int scrimColorOpaque = mScrimColor & 0xFF000000;
         return ColorUtils.getColorWithOverlay(color, scrimColorOpaque, fraction * scrimColorAlpha);
     }
-
-    private void waitForStatusBarColor(Activity activity, int expectedColor)
-            throws ExecutionException, TimeoutException {
-        CriteriaHelper.pollUiThread(() -> {
-            Criteria.checkThat(
-                    activity.getWindow().getStatusBarColor(), Matchers.is(expectedColor));
-        }, CriteriaHelper.DEFAULT_MAX_TIME_TO_POLL, CriteriaHelper.DEFAULT_POLLING_INTERVAL);
-    }
 }