Fix 3511340: Exit widget resize mode when home or back clicked

Also add an optimization to drastically reduce the number of
posted events when a widget is currently being resized.

Change-Id: I8839d4bba564028a67fb0355d35b7dd52465b199

src/com/android/launcher2/Workspace.java

@@ -1790,6 +1790,11 @@ public class Workspace extends SmoothPagedView
         }
     }
 
+    public void exitWidgetResizeMode() {
+        final CellLayout currentLayout = (CellLayout) getChildAt(getCurrentPage());
+        currentLayout.getChildrenLayout().clearAllResizeFrames();
+    }
+
     void unshrink(boolean animated) {
         unshrink(animated, false);
     }