Remove DocumentTabObserver and merge task description updates

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.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.webapps;
 
 import android.content.Intent;
 import android.graphics.Bitmap;
 import android.graphics.Color;
 import android.graphics.drawable.Drawable;
@@ skipping 45 matching lines @@
     private boolean mOldWebappCleanupStarted;
 
     private ViewGroup mSplashScreen;
     private WebappUrlBar mUrlBar;
 
     private boolean mIsInitialized;
     private Integer mBrandColor;
 
     private WebappUma mWebappUma;
 
+    private Bitmap mLargestFavicon;
+
     /**
      * Construct all the variables that shouldn't change.  We do it here both to clarify when the
      * objects are created and to ensure that they exist throughout the parallelized initialization
      * of the WebappActivity.
      */
     public WebappActivity() {
         mWebappInfo = WebappInfo.createEmpty();
         mDirectoryManager = new WebappDirectoryManager();
         mWebappUma = new WebappUma();
     }
@@ skipping 204 matching lines @@
         mUrlBar.update(tab.getUrl(), tab.getSecurityLevel());
     }
 
     private boolean isWebappDomain() {
         return UrlUtilities.sameDomainOrHost(
                 getActivityTab().getUrl(), getWebappInfo().uri().toString(), true);
     }
 
     protected TabObserver createTabObserver() {
         return new EmptyTabObserver() {
+
             @Override
             public void onSSLStateUpdated(Tab tab) {
                 updateUrlBar();
             }
 
             @Override
             public void onDidStartProvisionalLoadForFrame(
                     Tab tab, long frameId, long parentFrameId, boolean isMainFrame,
                     String validatedUrl, boolean isErrorPage, boolean isIframeSrcdoc) {
                 if (isMainFrame) updateUrlBar();
             }
 
             @Override
             public void onDidChangeThemeColor(Tab tab, int color) {
                 if (!isWebappDomain()) return;
                 mBrandColor = color;
                 updateTaskDescription();
             }
 
             @Override
             public void onTitleUpdated(Tab tab) {
                 if (!isWebappDomain()) return;
                 updateTaskDescription();
             }
 
             @Override
-            public void onFaviconUpdated(Tab tab) {
+            public void onFaviconUpdated(Tab tab, Bitmap icon) {
                 if (!isWebappDomain()) return;
-                updateTaskDescription();
+                if (mWebappInfo.icon() != null) return;

[gone, 2015/11/20 23:37:13]

Why'd this new condition appear?  Seems like we should be updating the task
description, regardless of this.

[Yusuf, 2015/11/20 23:38:54]

See updateTaskDescription where if there is an icon inside WebappInfo we always
use that instead of the favicon. Having this early return here avoid making a
bitmap copy for sites that has an icon inside webappinfo.

[Yusuf, 2015/11/20 23:47:33]

Done.

+                if (mLargestFavicon == null || icon.getWidth() > mLargestFavicon.getWidth()
+                        || icon.getHeight() > mLargestFavicon.getHeight()) {
+                    mLargestFavicon = icon;
+                    updateTaskDescription();
+                }
             }
 
             @Override
             public void onDidNavigateMainFrame(Tab tab, String url, String baseUrl,
                     boolean isNavigationToDifferentPage, boolean isNavigationInPage,
                     int statusCode) {
                 updateUrlBar();
             }
 
             @Override
@@ skipping 55 matching lines @@
         if (!TextUtils.isEmpty(mWebappInfo.shortName())) {
             title = mWebappInfo.shortName();
         } else if (getActivityTab() != null) {
             title = getActivityTab().getTitle();
         }
 
         Bitmap icon = null;
         if (mWebappInfo.icon() != null) {
             icon = mWebappInfo.icon();
         } else if (getActivityTab() != null) {
-            icon = getActivityTab().getFavicon();
+            icon = mLargestFavicon;
         }
 
         if (mBrandColor == null && mWebappInfo.hasValidThemeColor()) {
             mBrandColor = (int) mWebappInfo.themeColor();
         }
 
         int taskDescriptionColor =
                 ApiCompatibilityUtils.getColor(getResources(), R.color.default_primary_color);
         int statusBarColor = Color.BLACK;
         if (mBrandColor != null) {
@@ skipping 94 matching lines @@
         return visible;
     }
 
     // We're temporarily disable CS on webapp since there are some issues. (http://crbug.com/471950)
     // TODO(changwan): re-enable it once the issues are resolved.
     @Override
     protected boolean isContextualSearchAllowed() {
         return false;
     }
 }