[EoC] Restrict EoC to ChromeTabbedActivity

Prevent the contextual suggestions bottom sheet from appearing in CCTs
and other sub-classes of ChromeActivity that aren't ChromeTabbedActivity.

BUG=823987

Change-Id: I56c4ccfbc30ae078668d39cd8252e74468ae4dd7
Reviewed-on: https://chromium-review.googlesource.com/1005497Reviewed-by: Ted Choc <tedchoc@chromium.org>
Commit-Queue: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549592}

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

@@ -1289,7 +1289,8 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
                     mCompositorViewHolder.getLayoutManager(), coordinator);
         }
 
-        if (FeatureUtilities.isContextualSuggestionsBottomSheetEnabled(isTablet())) {
+        if (supportsContextualSuggestionsBottomSheet()
+                && FeatureUtilities.isContextualSuggestionsBottomSheetEnabled(isTablet())) {
             ViewGroup coordinator = (ViewGroup) findViewById(R.id.coordinator);
             getLayoutInflater().inflate(R.layout.bottom_sheet, coordinator);
             mBottomSheet = coordinator.findViewById(R.id.bottom_sheet);
@@ -2280,6 +2281,13 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
         return false;
     }
 
+    /**
+     * @return Whether this Activity supports showing contextual suggestions in a bottom sheet.
+     */
+    public boolean supportsContextualSuggestionsBottomSheet() {
+        return false;
+    }
+
     /**
      * @return the reference pool for this activity.
      * @deprecated Use {@link ChromeApplication#getReferencePool} instead.

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

@@ -2345,6 +2345,11 @@ public class ChromeTabbedActivity
         return true;
     }
 
+    @Override
+    public boolean supportsContextualSuggestionsBottomSheet() {
+        return true;
+    }
+
     @Override
     public void onScreenshotTaken() {
         Tracker tracker = TrackerFactory.getTrackerForProfile(Profile.getLastUsedProfile());