Android: Use a single TabDelegateFactory per ChromeActivity

A single factory instance for TabDelegate objects is enough for a
ChromeActivity. This CL prevents multiple instantiations of the factory.
This fixes a bug that logs MobileNTPOpenedInNewTab more often
than expected due to numerous UMA reporter objects.

Bug: 1014382
Change-Id: I7c28f6cd500bc58a835c16d7e5dbb6f9e90d82b2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2554274
Commit-Queue: Jinsuk Kim <jinsukkim@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830498}

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

@@ -305,6 +305,7 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
             new ObservableSupplierImpl<>();
 
     private CallbackController mCallbackController = new CallbackController();
+    private TabbedModeTabDelegateFactory mTabDelegateFactory;
 
     private final IncognitoTabHost mIncognitoTabHost = new IncognitoTabHost() {
         @Override
@@ -1651,15 +1652,19 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
                 mBookmarkBridgeSupplier, getModalDialogManager());
     }
 
-    @Override
-    protected Pair<ChromeTabCreator, ChromeTabCreator> createTabCreators() {
-        Supplier<TabDelegateFactory> tabDelegateFactorySupplier = () -> {
-            return new TabbedModeTabDelegateFactory(this, getAppBrowserControlsVisibilityDelegate(),
-                    getShareDelegateSupplier(), mEphemeralTabCoordinatorSupplier,
+    private TabDelegateFactory getTabDelegateFactory() {
+        if (mTabDelegateFactory == null) {
+            mTabDelegateFactory = new TabbedModeTabDelegateFactory(this,
+                    getAppBrowserControlsVisibilityDelegate(), getShareDelegateSupplier(),
+                    mEphemeralTabCoordinatorSupplier,
                     ((TabbedRootUiCoordinator) mRootUiCoordinator)::onContextMenuCopyLink,
                     mRootUiCoordinator.getBottomSheetController());
-        };
+        }
+        return mTabDelegateFactory;
+    }
 
+    @Override
+    protected Pair<ChromeTabCreator, ChromeTabCreator> createTabCreators() {
         ChromeTabCreator.OverviewNTPCreator overviewNTPCreator = null;
 
         if (StartSurfaceConfiguration.isStartSurfaceEnabled()) {
@@ -1676,10 +1681,10 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
             };
         }
         return Pair.create(new ChromeTabCreator(this, getWindowAndroid(), getStartupTabPreloader(),
-                                   tabDelegateFactorySupplier, false, overviewNTPCreator,
+                                   this::getTabDelegateFactory, false, overviewNTPCreator,
                                    AsyncTabParamsManagerSingleton.getInstance()),
                 new ChromeTabCreator(this, getWindowAndroid(), getStartupTabPreloader(),
-                        tabDelegateFactorySupplier, true, overviewNTPCreator,
+                        this::getTabDelegateFactory, true, overviewNTPCreator,
                         AsyncTabParamsManagerSingleton.getInstance()));
     }
 
@@ -2158,6 +2163,7 @@ public class ChromeTabbedActivity extends ChromeActivity<ChromeActivityComponent
         ChromeAccessibilityUtil.get().removeObserver(this);
         ChromeAccessibilityUtil.get().removeObserver(mLayoutManager);
 
+        if (mTabDelegateFactory != null) mTabDelegateFactory.destroy();
         super.onDestroyInternal();
     }
 

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

@@ -85,4 +85,9 @@ public class TabbedModeTabDelegateFactory implements TabDelegateFactory {
         }
         return mNativePageFactory.createNativePage(url, candidatePage, tab);
     }
+
+    /** Destroy and unhook objects at destruction. */
+    public void destroy() {
+        if (mNativePageFactory != null) mNativePageFactory.destroy();
+    }
 }

chrome/android/java/src/org/chromium/chrome/browser/native_page/NativePageFactory.java

@@ -229,4 +229,9 @@ public class NativePageFactory {
             return new BrowserControlsMarginSupplier(mBrowserControlsStateProvider);
         }
     }
+
+    /** Destroy and unhook objects at destruction. */
+    public void destroy() {
+        if (mNewTabPageUma != null) mNewTabPageUma.destroy();
+    }
 }

chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageUma.java

@@ -156,6 +156,7 @@ public class NewTabPageUma {
     private final Supplier<Long> mLastInteractionTime;
     private final boolean mActivityHadWarmStart;
     private final Supplier<Intent> mActivityIntent;
+    private TabCreationRecorder mTabCreationRecorder;
 
     /**
      * Constructor.
@@ -216,7 +217,8 @@ public class NewTabPageUma {
      * users navigate back to already opened NTPs.
      */
     public void monitorNTPCreation() {
-        mTabModelSelector.addObserver(new TabCreationRecorder());
+        mTabCreationRecorder = new TabCreationRecorder();
+        mTabModelSelector.addObserver(mTabCreationRecorder);
     }
 
     /**
@@ -321,4 +323,9 @@ public class NewTabPageUma {
             }
         });
     }
+
+    /** Destroy and unhook objects at destruction. */
+    public void destroy() {
+        if (mTabCreationRecorder != null) mTabModelSelector.removeObserver(mTabCreationRecorder);
+    }
 }