[StartSurface] Refactor and make MV tiles available on all start surfaces

This is the first patch of splitting the bigger one
https://chromium-review.googlesource.com/c/chromium/src/+/1797069

Screenshots:
https://drive.google.com/file/d/1bmR-hfo1XQsaB61MbGUSmRjAIOyypaEj/view?usp=sharing
https://drive.google.com/file/d/1opItnNVwGI-eRJxlN6M2hxurS88D4btX/view?usp=sharing
https://drive.google.com/file/d/1ElJLgbogCb-f-D5vO6hmjC5SznxxWZKc/view?usp=sharing
https://drive.google.com/file/d/1RU88SHUqFqSu_VhxrdyfVTSSWJcMdn3i/view?usp=sharing
https://drive.google.com/file/d/1JQZAiFVOcQSeU9N8XOK7Zyh7TL5xT6Vk/view?usp=sharing

Bug: 982018
Change-Id: Iec9086c6538d29208ba92b106985bb04f0148983
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1817106
Commit-Queue: Ganggui Tang <gogerald@chromium.org>
Reviewed-by: Yusuf Ozuysal <yusufo@chromium.org>
Auto-Submit: Ganggui Tang <gogerald@chromium.org>
Cr-Commit-Position: refs/heads/master@{#701715}

chrome/android/features/start_surface/internal/BUILD.gn

@@ -89,6 +89,8 @@ android_library("java") {
     "java/src/org/chromium/chrome/features/start_surface/StartSurfaceLayout.java",
     "java/src/org/chromium/chrome/features/start_surface/StartSurfaceMediator.java",
     "java/src/org/chromium/chrome/features/start_surface/StartSurfaceProperties.java",
+    "java/src/org/chromium/chrome/features/start_surface/SecondaryTasksSurfaceViewBinder.java",
+    "java/src/org/chromium/chrome/features/start_surface/TasksSurfaceViewBinder.java",
   ]
 
   deps = [

chrome/android/features/start_surface/internal/java/src/org/chromium/chrome/features/start_surface/SecondaryTasksSurfaceViewBinder.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.features.start_surface;
+
+import static org.chromium.chrome.features.start_surface.StartSurfaceProperties.IS_SECONDARY_SURFACE_VISIBLE;
+import static org.chromium.chrome.features.start_surface.StartSurfaceProperties.IS_SHOWING_OVERVIEW;
+import static org.chromium.chrome.features.start_surface.StartSurfaceProperties.TOP_BAR_HEIGHT;
+
+import android.view.View;
+import android.view.ViewGroup.MarginLayoutParams;
+
+import org.chromium.ui.modelutil.PropertyKey;
+import org.chromium.ui.modelutil.PropertyModel;
+
+/** The binder controls the display of the secondary {@link TasksView} in its parent. */
+class SecondaryTasksSurfaceViewBinder {
+    public static void bind(PropertyModel model, TasksSurfaceViewBinder.ViewHolder viewHolder,
+            PropertyKey propertyKey) {
+        if (IS_SECONDARY_SURFACE_VISIBLE == propertyKey) {
+            setVisibility(viewHolder, model,
+                    model.get(IS_SHOWING_OVERVIEW) && model.get(IS_SECONDARY_SURFACE_VISIBLE));
+        } else if (IS_SHOWING_OVERVIEW == propertyKey) {
+            setVisibility(viewHolder, model,
+                    model.get(IS_SHOWING_OVERVIEW) && model.get(IS_SECONDARY_SURFACE_VISIBLE));
+        }
+    }
+
+    private static void setVisibility(
+            TasksSurfaceViewBinder.ViewHolder viewHolder, PropertyModel model, boolean isShowing) {
+        if (isShowing && viewHolder.tasksSurfaceView.getParent() == null) {
+            MarginLayoutParams layoutParams =
+                    (MarginLayoutParams) viewHolder.scrollContainer.getLayoutParams();
+            layoutParams.topMargin = model.get(TOP_BAR_HEIGHT);
+            viewHolder.parentView.addView(viewHolder.scrollContainer);
+            viewHolder.scrollContainer.addView(viewHolder.tasksSurfaceView);
+        }
+
+        viewHolder.scrollContainer.setVisibility(isShowing ? View.VISIBLE : View.GONE);
+    }
+}

chrome/android/features/start_surface/internal/java/src/org/chromium/chrome/features/start_surface/StartSurfaceLayout.java

@@ -146,10 +146,6 @@ public class StartSurfaceLayout extends Layout implements StartSurface.OverviewM
         if (mController != null) {
             mController.removeOverviewModeObserver(this);
         }
-
-        if (mStartSurface != null) {
-            mStartSurface.destroy();
-        }
     }
 
     @Override

chrome/android/features/start_surface/internal/java/src/org/chromium/chrome/features/start_surface/StartSurfaceProperties.java

@@ -32,6 +32,8 @@ class StartSurfaceProperties {
             new PropertyModel.WritableBooleanPropertyKey();
     public static final PropertyModel.WritableBooleanPropertyKey IS_EXPLORE_SURFACE_VISIBLE =
             new PropertyModel.WritableBooleanPropertyKey();
+    public static final PropertyModel.WritableBooleanPropertyKey IS_SECONDARY_SURFACE_VISIBLE =
+            new PropertyModel.WritableBooleanPropertyKey();
     public static final PropertyModel.WritableBooleanPropertyKey IS_SHOWING_OVERVIEW =
             new PropertyModel.WritableBooleanPropertyKey();
     public static final PropertyModel
@@ -41,6 +43,6 @@ class StartSurfaceProperties {
             new PropertyModel.WritableIntPropertyKey();
     public static final PropertyKey[] ALL_KEYS = new PropertyKey[] {BOTTOM_BAR_CLICKLISTENER,
             BOTTOM_BAR_HEIGHT, BOTTOM_BAR_SELECTED_TAB_POSITION, IS_BOTTOM_BAR_VISIBLE,
-            IS_EXPLORE_SURFACE_VISIBLE, IS_SHOWING_OVERVIEW, FEED_SURFACE_COORDINATOR,
-            TOP_BAR_HEIGHT};
+            IS_EXPLORE_SURFACE_VISIBLE, IS_SECONDARY_SURFACE_VISIBLE, IS_SHOWING_OVERVIEW,
+            FEED_SURFACE_COORDINATOR, TOP_BAR_HEIGHT};
 }

chrome/android/features/start_surface/internal/java/src/org/chromium/chrome/features/start_surface/TasksSurfaceViewBinder.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.features.start_surface;
+
+import static org.chromium.chrome.features.start_surface.StartSurfaceProperties.BOTTOM_BAR_HEIGHT;
+import static org.chromium.chrome.features.start_surface.StartSurfaceProperties.IS_SHOWING_OVERVIEW;
+import static org.chromium.chrome.features.start_surface.StartSurfaceProperties.TOP_BAR_HEIGHT;
+
+import android.support.v4.widget.NestedScrollView;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewGroup.MarginLayoutParams;
+
+import androidx.annotation.Nullable;
+
+import org.chromium.ui.modelutil.PropertyKey;
+import org.chromium.ui.modelutil.PropertyModel;
+
+/** The binder controls the display of the {@link TasksView} in its parent. */
+class TasksSurfaceViewBinder {
+    /**
+     * The view holder holds the parent view, the scroll container and the tasks surface view.
+     */
+    public static class ViewHolder {
+        public final ViewGroup parentView;
+        @Nullable
+        public final NestedScrollView scrollContainer;
+        public final ViewGroup tasksSurfaceView;
+
+        ViewHolder(ViewGroup parentView, @Nullable NestedScrollView scrollContainer,
+                ViewGroup tasksSurfaceView) {
+            this.parentView = parentView;
+            this.scrollContainer = scrollContainer;
+            this.tasksSurfaceView = tasksSurfaceView;
+        }
+    }
+
+    public static void bind(PropertyModel model, ViewHolder viewHolder, PropertyKey propertyKey) {
+        if (IS_SHOWING_OVERVIEW == propertyKey) {
+            updateLayoutAndVisibility(viewHolder, model, model.get(IS_SHOWING_OVERVIEW));
+        } else if (BOTTOM_BAR_HEIGHT == propertyKey) {
+            setBottomBarHeight(viewHolder, model.get(BOTTOM_BAR_HEIGHT));
+        }
+    }
+
+    private static void updateLayoutAndVisibility(
+            ViewHolder viewHolder, PropertyModel model, boolean isShowing) {
+        ViewGroup targetView = viewHolder.scrollContainer == null ? viewHolder.tasksSurfaceView
+                                                                  : viewHolder.scrollContainer;
+        if (isShowing && viewHolder.tasksSurfaceView.getParent() == null) {
+            viewHolder.parentView.addView(targetView);
+            if (viewHolder.scrollContainer != null) targetView.addView(viewHolder.tasksSurfaceView);
+            MarginLayoutParams layoutParams = (MarginLayoutParams) targetView.getLayoutParams();
+            layoutParams.bottomMargin = model.get(BOTTOM_BAR_HEIGHT);
+            layoutParams.topMargin = model.get(TOP_BAR_HEIGHT);
+        }
+
+        targetView.setVisibility(isShowing ? View.VISIBLE : View.GONE);
+    }
+
+    private static void setBottomBarHeight(ViewHolder viewHolder, int height) {
+        ViewGroup targetView = viewHolder.scrollContainer == null ? viewHolder.tasksSurfaceView
+                                                                  : viewHolder.scrollContainer;
+        ((MarginLayoutParams) targetView.getLayoutParams()).bottomMargin = height;
+    }
+}

chrome/android/features/start_surface/public/java/src/org/chromium/chrome/features/start_surface/StartSurface.java

@@ -92,9 +92,4 @@ public interface StartSurface {
      * @return TabListDelegate implementation that can be used to access the Tab List.
      */
     TabSwitcher.TabListDelegate getTabListDelegate();
-
-    /**
-     * Perform any necessary cleanup.
-     */
-    void destroy();
 }
\ No newline at end of file

chrome/android/features/tab_ui/BUILD.gn

@@ -78,9 +78,7 @@ android_resources("java_resources") {
 android_library("java") {
   java_files = [
     "java/src/org/chromium/chrome/browser/tasks/MostVisitedListCoordinator.java",
-    "java/src/org/chromium/chrome/browser/tasks/MostVisitedListMediator.java",
     "java/src/org/chromium/chrome/browser/tasks/MostVisitedListViewBinder.java",
-    "java/src/org/chromium/chrome/browser/tasks/MostVisitedListProperties.java",
     "java/src/org/chromium/chrome/browser/tasks/TasksSurfaceMediator.java",
     "java/src/org/chromium/chrome/browser/tasks/TasksSurfaceCoordinator.java",
     "java/src/org/chromium/chrome/browser/tasks/TasksView.java",

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/MostVisitedListCoordinator.java

@@ -44,18 +44,15 @@ class MostVisitedListCoordinator implements TileGroup.Observer, TileGroup.TileSe
     // There's a limit of 12 in {@link MostVisitedSitesBridge#setObserver}.
     private static final int MAX_RESULTS = 12;
     private PropertyModelChangeProcessor mModelChangeProcessor;
-    private MostVisitedListMediator mMediator;
     private TileGroup mTileGroup;
     private TileRenderer mRenderer;
     private ViewGroup mParent;
 
-    public MostVisitedListCoordinator(ChromeActivity activity, ViewGroup parent) {
-        PropertyModel propertyModel = new PropertyModel(MostVisitedListProperties.ALL_KEYS);
+    public MostVisitedListCoordinator(
+            ChromeActivity activity, ViewGroup parent, PropertyModel propertyModel) {
         mModelChangeProcessor = PropertyModelChangeProcessor.create(
                 propertyModel, parent, MostVisitedListViewBinder::bind);
 
-        mMediator = new MostVisitedListMediator(propertyModel, activity.getTabModelSelector());
-
         mParent = parent;
         Profile profile = Profile.getLastUsedProfile();
         SuggestionsSource suggestionsSource =
@@ -82,10 +79,6 @@ class MostVisitedListCoordinator implements TileGroup.Observer, TileGroup.TileSe
         mTileGroup.startObserving(MAX_RESULTS);
     }
 
-    void destroy() {
-        mMediator.destroy();
-    }
-
     private void updateTileIcon(Tile tile) {
         for (int i = 0; i < mParent.getChildCount(); i++) {
             View tileView = mParent.getChildAt(i);

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/MostVisitedListMediator.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.tasks;
-
-import static org.chromium.chrome.browser.tasks.MostVisitedListProperties.IS_VISIBLE;
-
-import org.chromium.chrome.browser.tabmodel.EmptyTabModelSelectorObserver;
-import org.chromium.chrome.browser.tabmodel.TabModel;
-import org.chromium.chrome.browser.tabmodel.TabModelSelector;
-import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver;
-import org.chromium.ui.modelutil.PropertyModel;
-
-/** Mediator handling logic and model operations for most visited list. */
-class MostVisitedListMediator {
-    private final PropertyModel mModel;
-    private final TabModelSelector mTabModelSelector;
-    private final TabModelSelectorObserver mTabModelSelectorObserver;
-
-    MostVisitedListMediator(PropertyModel model, TabModelSelector tabModelSelector) {
-        mModel = model;
-        mTabModelSelector = tabModelSelector;
-
-        mTabModelSelectorObserver = new EmptyTabModelSelectorObserver() {
-            @Override
-            public void onTabModelSelected(TabModel newModel, TabModel oldModel) {
-                mModel.set(IS_VISIBLE, !newModel.isIncognito());
-            }
-        };
-        mTabModelSelector.addObserver(mTabModelSelectorObserver);
-    }
-
-    void destroy() {
-        mTabModelSelector.removeObserver(mTabModelSelectorObserver);
-    }
-}

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/TasksSurface.java

@@ -36,9 +36,4 @@ public interface TasksSurface {
      * @return The surface's container {@link ViewGroup}.
      */
     ViewGroup getContainerView();
-
-    /**
-     * Perform any necessary cleanup.
-     */
-    void destroy();
 }

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/TasksSurfaceCoordinator.java

@@ -39,11 +39,10 @@ public class TasksSurfaceCoordinator implements TasksSurface {
                     activity, mView.getTabSwitcherContainer());
         }
 
-        mMediator = new TasksSurfaceMediator(
-                activity, propertyModel, isTabCarousel, activity.getOverviewModeBehavior());
+        mMediator = new TasksSurfaceMediator(activity, propertyModel, isTabCarousel);
 
         LinearLayout mvTilesLayout = mView.findViewById(R.id.mv_tiles_layout);
-        mMostVisitedList = new MostVisitedListCoordinator(activity, mvTilesLayout);
+        mMostVisitedList = new MostVisitedListCoordinator(activity, mvTilesLayout, propertyModel);
     }
 
     /** TasksSurface implementation. */
@@ -66,10 +65,4 @@ public class TasksSurfaceCoordinator implements TasksSurface {
     public ViewGroup getContainerView() {
         return mView;
     }
-
-    @Override
-    public void destroy() {
-        mMediator.destroy();
-        mMostVisitedList.destroy();
-    }
 }

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/TasksSurfaceMediator.java

@@ -5,63 +5,19 @@
 package org.chromium.chrome.browser.tasks;
 
 import static org.chromium.chrome.browser.tasks.TasksSurfaceProperties.IS_TAB_CAROUSEL;
-import static org.chromium.chrome.browser.tasks.TasksSurfaceProperties.MV_TILES_VISIBLE;
-import static org.chromium.chrome.browser.tasks.TasksSurfaceProperties.TOP_PADDING;
 
 import android.content.Context;
 
-import org.chromium.chrome.R;
-import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.ui.modelutil.PropertyModel;
 
 /**
  * Mediator for handling {@link TasksSurface}-related logic.
  */
-class TasksSurfaceMediator implements OverviewModeBehavior.OverviewModeObserver {
+class TasksSurfaceMediator {
     private final PropertyModel mModel;
 
-    private OverviewModeBehavior mOverviewModeBehavior;
-
-    TasksSurfaceMediator(Context context, PropertyModel model, boolean isTabCarousel,
-            OverviewModeBehavior overviewModeBehavior) {
+    TasksSurfaceMediator(Context context, PropertyModel model, boolean isTabCarousel) {
         mModel = model;
-
         mModel.set(IS_TAB_CAROUSEL, isTabCarousel);
-
-        if (!isTabCarousel) {
-            mModel.set(TOP_PADDING,
-                    context.getResources().getDimensionPixelSize(R.dimen.toolbar_height_no_shadow)
-                            * 2);
-        }
-
-        // TODO(mattsimmons): Move all of the tasks surface visibility changes here and handle it
-        //  for all surface variations. This is not ideal as-is.
-        if (ReturnToChromeExperimentsUtil.shouldShowMostVisitedOnTabSwitcher()) {
-            mOverviewModeBehavior = overviewModeBehavior;
-            mOverviewModeBehavior.addOverviewModeObserver(this);
-        }
-    }
-
-    @Override
-    public void onOverviewModeStartedShowing(boolean showToolbar) {
-        mModel.set(MV_TILES_VISIBLE, true);
-    }
-
-    @Override
-    public void onOverviewModeFinishedShowing() {}
-
-    @Override
-    public void onOverviewModeStartedHiding(boolean showToolbar, boolean delayAnimation) {
-        mModel.set(MV_TILES_VISIBLE, false);
-    }
-
-    @Override
-    public void onOverviewModeFinishedHiding() {}
-
-    void destroy() {
-        if (mOverviewModeBehavior != null) {
-            mOverviewModeBehavior.removeOverviewModeObserver(this);
-            mOverviewModeBehavior = null;
-        }
     }
 }

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/TasksSurfaceProperties.java

@@ -4,6 +4,8 @@
 
 package org.chromium.chrome.browser.tasks;
 
+import static org.chromium.chrome.browser.tasks.MostVisitedListProperties.IS_VISIBLE;
+
 import android.view.View;
 
 import org.chromium.ui.modelutil.PropertyKey;
@@ -11,15 +13,14 @@ import org.chromium.ui.modelutil.PropertyModel;
 
 /** List of the tasks surface properties. */
 public class TasksSurfaceProperties {
+    private TasksSurfaceProperties() {}
+
     public static final PropertyModel.WritableBooleanPropertyKey IS_TAB_CAROUSEL =
             new PropertyModel.WritableBooleanPropertyKey();
     public static final PropertyModel
             .WritableObjectPropertyKey<View.OnClickListener> MORE_TABS_CLICK_LISTENER =
             new PropertyModel.WritableObjectPropertyKey<View.OnClickListener>();
-    public static final PropertyModel.WritableBooleanPropertyKey MV_TILES_VISIBLE =
-            new PropertyModel.WritableBooleanPropertyKey();
-    public static final PropertyModel.WritableIntPropertyKey TOP_PADDING =
-            new PropertyModel.WritableIntPropertyKey();
-    public static final PropertyKey[] ALL_KEYS = new PropertyKey[] {
-            IS_TAB_CAROUSEL, MORE_TABS_CLICK_LISTENER, MV_TILES_VISIBLE, TOP_PADDING};
+    public static final PropertyModel.WritableBooleanPropertyKey MV_TILES_VISIBLE = IS_VISIBLE;
+    public static final PropertyKey[] ALL_KEYS =
+            new PropertyKey[] {IS_TAB_CAROUSEL, MORE_TABS_CLICK_LISTENER, MV_TILES_VISIBLE};
 }

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/TasksViewBinder.java

@@ -7,7 +7,6 @@ package org.chromium.chrome.browser.tasks;
 import static org.chromium.chrome.browser.tasks.TasksSurfaceProperties.IS_TAB_CAROUSEL;
 import static org.chromium.chrome.browser.tasks.TasksSurfaceProperties.MORE_TABS_CLICK_LISTENER;
 import static org.chromium.chrome.browser.tasks.TasksSurfaceProperties.MV_TILES_VISIBLE;
-import static org.chromium.chrome.browser.tasks.TasksSurfaceProperties.TOP_PADDING;
 
 import android.view.View;
 
@@ -23,8 +22,6 @@ class TasksViewBinder {
             view.setMoreTabsOnClickListener(model.get(MORE_TABS_CLICK_LISTENER));
         } else if (propertyKey == MV_TILES_VISIBLE) {
             view.setMostVisitedVisibility(model.get(MV_TILES_VISIBLE) ? View.VISIBLE : View.GONE);
-        } else if (propertyKey == TOP_PADDING) {
-            view.setPadding(0, model.get(TOP_PADDING), 0, 0);
         }
     }
 }
\ No newline at end of file

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabSwitcher.java

@@ -100,12 +100,6 @@ public interface TabSwitcher {
          * @return Whether or not the TabSwitcher consumed the event.
          */
         boolean onBackPressed();
-
-        /**
-         * Set the bottom control height to margin the bottom of the TabListRecyclerView.
-         * @param bottomControlsHeight The bottom control height in pixel.
-         */
-        void setBottomControlsHeight(int bottomControlsHeight);
     }
 
     /**

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabSwitcherMediator.java

@@ -504,11 +504,6 @@ class TabSwitcherMediator implements TabSwitcher.Controller, TabListRecyclerView
         return true;
     }
 
-    @Override
-    public void setBottomControlsHeight(int bottomControlsHeight) {
-        mContainerViewModel.set(BOTTOM_CONTROLS_HEIGHT, bottomControlsHeight);
-    }
-
     /**
      * Do clean-up work after the overview hiding animation is finished.
      * @see TabSwitcher#postHiding

chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/MostVisitedListMediatorUnitTest.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.tasks;
-
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-import static org.mockito.Mockito.doReturn;
-import static org.mockito.Mockito.verify;
-
-import static org.chromium.chrome.browser.tasks.MostVisitedListProperties.IS_VISIBLE;
-
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.ArgumentCaptor;
-import org.mockito.Captor;
-import org.mockito.Mock;
-import org.mockito.MockitoAnnotations;
-
-import org.chromium.chrome.browser.tabmodel.TabModel;
-import org.chromium.chrome.browser.tabmodel.TabModelSelector;
-import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver;
-import org.chromium.testing.local.LocalRobolectricTestRunner;
-import org.chromium.ui.modelutil.PropertyModel;
-
-/**
- * Tests for {@link MostVisitedListMediator}.
- */
-@RunWith(LocalRobolectricTestRunner.class)
-public final class MostVisitedListMediatorUnitTest {
-    private final PropertyModel mModel = new PropertyModel(MostVisitedListProperties.ALL_KEYS);
-
-    @Mock
-    private TabModel mNewTabModel;
-
-    @Mock
-    private TabModelSelector mTabModelSelector;
-
-    @Captor
-    private ArgumentCaptor<TabModelSelectorObserver> mTabModelSelectorObserverCaptor;
-
-    private MostVisitedListMediator mMediator;
-
-    @Before
-    public void setUp() {
-        MockitoAnnotations.initMocks(this);
-
-        mMediator = new MostVisitedListMediator(mModel, mTabModelSelector);
-
-        verify(mTabModelSelector).addObserver(mTabModelSelectorObserverCaptor.capture());
-    }
-
-    @Test
-    public void incognitoTabModel_setsNotVisible() {
-        mModel.set(IS_VISIBLE, true);
-        doReturn(true).when(mNewTabModel).isIncognito();
-
-        mTabModelSelectorObserverCaptor.getValue().onTabModelSelected(mNewTabModel, null);
-
-        assertFalse(mModel.get(IS_VISIBLE));
-    }
-
-    @Test
-    public void regularTabModel_setsVisible() {
-        mModel.set(IS_VISIBLE, false);
-        doReturn(false).when(mNewTabModel).isIncognito();
-
-        mTabModelSelectorObserverCaptor.getValue().onTabModelSelected(mNewTabModel, null);
-
-        assertTrue(mModel.get(IS_VISIBLE));
-    }
-}

chrome/android/features/tab_ui/tab_management_java_sources.gni

@@ -6,6 +6,7 @@ import(
     "//chrome/android/features/start_surface/public/start_surface_public_java_sources.gni")
 
 public_tab_management_java_sources = [
+  "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/MostVisitedListProperties.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/TasksSurface.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/TasksSurfaceProperties.java",
   "//chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_groups/TabGroupModelFilter.java",
@@ -31,7 +32,6 @@ tab_management_test_java_sources = [
 ]
 
 tab_management_junit_java_sources = [
-  "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/MostVisitedListMediatorUnitTest.java",
   "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/MostVisitedListViewBinderUnitTest.java",
   "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/tab_groups/TabGroupModelFilterUnitTest.java",
   "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/tab_management/TabSwitcherMediatorUnitTest.java",

chrome/android/java/src/org/chromium/chrome/browser/tasks/ReturnToChromeExperimentsUtil.java

@@ -68,19 +68,6 @@ public final class ReturnToChromeExperimentsUtil {
                 && ChromeFeatureList.isEnabled(ChromeFeatureList.START_SURFACE_ANDROID);
     }
 
-    /**
-     * TODO(mattsimmons): Merge this with the one above once all the surface variations work
-     *  correctly with mv tiles, omnibox, etc. (both should be true when != NO_START_SURFACE)
-     * @return Whether we show the most visited tiles on the tab switcher.
-     */
-    public static boolean shouldShowMostVisitedOnTabSwitcher() {
-        return ChromeFeatureList.isInitialized()
-                && ChromeFeatureList
-                           .getFieldTrialParamByFeature(ChromeFeatureList.START_SURFACE_ANDROID,
-                                   "start_surface_variation")
-                           .equals("tasksonly");
-    }
-
     /**
      * Check if we should handle the navigation. If so, create a new tab and load the URL.
      *