Remove DocumentTabObserver and merge task description updates

chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java

Index: chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java b/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
index 309d49f3a7f81d7a7dce79110d6c55b0ecba8194..a0d54a30ddb2c16420bbb1d154ac9ec84fb83753 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
@@ -71,6 +71,7 @@ import org.chromium.chrome.browser.tabmodel.TabModel.TabLaunchType;
 import org.chromium.chrome.browser.tabmodel.TabModel.TabSelectionType;
 import org.chromium.chrome.browser.tabmodel.TabModelImpl;
 import org.chromium.chrome.browser.util.AccessibilityUtil;
+import org.chromium.chrome.browser.util.FeatureUtilities;
 import org.chromium.components.dom_distiller.core.DomDistillerUrlUtils;
 import org.chromium.components.navigation_interception.InterceptNavigationDelegate;
 import org.chromium.content.browser.ActivityContentVideoViewClient;
@@ -1806,7 +1807,7 @@ public class Tab implements ViewGroup.OnHierarchyChangeListener,
     private void notifyFaviconChanged() {
         RewindableIterator<TabObserver> observers = getTabObservers();
         while (observers.hasNext()) {
-            observers.next().onFaviconUpdated(this);
+            observers.next().onFaviconUpdated(this, null);
         }
     }
 
@@ -2098,16 +2099,12 @@ public class Tab implements ViewGroup.OnHierarchyChangeListener,
                 && icon.getHeight() == mIdealFaviconSize)) {
             mFavicon = Bitmap.createScaledBitmap(icon, mIdealFaviconSize, mIdealFaviconSize, true);
             needUpdate = true;
-        }
-
-        if (pageUrlChanged) {
             mFaviconUrl = url;
-            needUpdate = true;
         }
 
-        if (!needUpdate) return;
+        if (!needUpdate && !FeatureUtilities.isDocumentMode(getApplicationContext())) return;

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

This early-exit logic looks strange.  Shouldn't the TabObservers be what
determines whether or not something should be done?

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

Done.

 
-        for (TabObserver observer : mObservers) observer.onFaviconUpdated(this);
+        for (TabObserver observer : mObservers) observer.onFaviconUpdated(this, icon);
     }
     /**
      * Called when the navigation entry containing the history item changed,