[Suggestions UI] Drop Bitmap references from articles under memory pressure.

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

 // Copyright 2015 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.ntp;
 
 import android.annotation.TargetApi;
 import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.Point;
 import android.graphics.Rect;
 import android.os.Build;
 import android.support.v4.view.ViewCompat;
 import android.support.v7.widget.RecyclerView;
 import android.text.TextUtils;
 import android.view.LayoutInflater;
 import android.view.View;
 
 import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.CommandLine;
+import org.chromium.base.DiscardableReferencePool;
 import org.chromium.base.Log;
 import org.chromium.base.TraceEvent;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.metrics.RecordUserAction;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.ChromeFeatureList;
 import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.NativePage;
@@ skipping 140 matching lines @@
     @VisibleForTesting
     public static void setSuggestionsSourceForTests(SuggestionsSource suggestionsSource) {
         sSuggestionsSourceForTests = suggestionsSource;
     }
 
     private class NewTabPageManagerImpl
             extends SuggestionsUiDelegateImpl implements NewTabPageManager {
         public NewTabPageManagerImpl(SuggestionsSource suggestionsSource,
                 SuggestionsEventReporter eventReporter,
                 SuggestionsNavigationDelegate navigationDelegate, Profile profile,
-                NativePageHost nativePageHost) {
-            super(suggestionsSource, eventReporter, navigationDelegate, profile, nativePageHost);
+                NativePageHost nativePageHost, DiscardableReferencePool referencePool) {
+            super(suggestionsSource, eventReporter, navigationDelegate, profile, nativePageHost,
+                    referencePool);
         }
 
         @Override
         public boolean isLocationBarShownInNTP() {
             if (mIsDestroyed) return false;
             Context context = mNewTabPageView.getContext();
             return isInSingleUrlBarMode(context)
                     && !mNewTabPageView.urlFocusAnimationsDisabled();
         }
 
@@ skipping 122 matching lines @@
         mTab = nativePageHost.getActiveTab();
         mTabModelSelector = tabModelSelector;
         Profile profile = mTab.getProfile();
 
         mSnippetsBridge = new SnippetsBridge(profile);
         SuggestionsEventReporter eventReporter = new SuggestionsEventReporterBridge();
 
         SuggestionsNavigationDelegateImpl navigationDelegate =
                 new SuggestionsNavigationDelegateImpl(
                         activity, profile, nativePageHost, tabModelSelector);
-        mNewTabPageManager = new NewTabPageManagerImpl(
-                mSnippetsBridge, eventReporter, navigationDelegate, profile, nativePageHost);
+        mNewTabPageManager = new NewTabPageManagerImpl(mSnippetsBridge, eventReporter,
+                navigationDelegate, profile, nativePageHost, activity.getReferencePool());
         mTileGroupDelegate = new NewTabPageTileGroupDelegate(
                 activity, profile, tabModelSelector, navigationDelegate);
 
         mTitle = activity.getResources().getString(R.string.button_new_tab);
         mBackgroundColor = ApiCompatibilityUtils.getColor(activity.getResources(), R.color.ntp_bg);
         mThemeColor = ApiCompatibilityUtils.getColor(
                 activity.getResources(), R.color.default_primary_color);
         TemplateUrlService.getInstance().addObserver(this);
 
         mTabObserver = new EmptyTabObserver() {
@@ skipping 273 matching lines @@
     @Override
     public boolean shouldCaptureThumbnail() {
         return mNewTabPageView.shouldCaptureThumbnail();
     }
 
     @Override
     public void captureThumbnail(Canvas canvas) {
         mNewTabPageView.captureThumbnail(canvas);
     }
 }