[Sync] Add support for identifying tabbed activites

chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
index 1134322623d8b7b1302330a7c055748d82e7ce3d..cae1d12a6effad1ec0035050230c2c6f3c73357d 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
@@ -40,6 +40,8 @@ public class TabModelSelectorImpl extends TabModelSelectorBase implements TabMod
 
     private boolean mIsUndoSupported;
 
+    private boolean mIsTabbedActivity;
+
     private final TabModelOrderController mOrderController;
 
     private OverviewModeBehavior mOverviewModeBehavior;
@@ -73,6 +75,7 @@ public class TabModelSelectorImpl extends TabModelSelectorBase implements TabMod
             }
         };
         mIsUndoSupported = supportUndo;
+        mIsTabbedActivity = persistencePolicy instanceof TabbedModeTabPersistencePolicy;
         mTabSaver = new TabPersistentStore(
                 persistencePolicy, this, mTabCreatorManager, persistentStoreObserver);
         mOrderController = new TabModelOrderController(this);
@@ -389,6 +392,11 @@ public class TabModelSelectorImpl extends TabModelSelectorBase implements TabMod
         return mSessionRestoreInProgress.get();
     }
 
+    @Override
+    public boolean isTabbedActivity() {
+        return mIsTabbedActivity;
+    }
+
     // TODO(tedchoc): Remove the need for this to be exposed.
     @Override
     public void notifyChanged() {