Add an experimental standalone content suggestions UI.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageView.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageView.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageView.java
index 8412e5c9f3af3d51cffe0648f6fe39d7a0cbdfd6..fffd9faf99958c24d6426d3c6a3f71b739152102 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageView.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageView.java
@@ -361,8 +361,15 @@ public class NewTabPageView extends FrameLayout
             mScrollView.enableBottomShadow(SHADOW_COLOR);
             mNewTabPageLayout = (NewTabPageLayout) findViewById(R.id.ntp_content);
         }
-        mContextMenuManager =
-                new ContextMenuManager(mManager, tab, mUseCardsUi ? mRecyclerView : mScrollView);
+        mContextMenuManager = new ContextMenuManager(mActivity, mManager,
+                mUseCardsUi ? mRecyclerView : mScrollView);
+        mActivity.getWindowAndroid().addContextMenuCloseListener(mContextMenuManager);
+        manager.addDestructionObserver(new DestructionObserver() {
+            @Override
+            public void onDestroy() {
+                mActivity.getWindowAndroid().removeContextMenuCloseListener(mContextMenuManager);
+            }
+        });
 
         mMostVisitedDesign = new MostVisitedDesign(getContext());
         mMostVisitedLayout =