Add support for delete animation in LayoutAnimation on Android

Summary:
Android follow up to #6779

**Test plan**
Tested add/removing views in the UIExample explorer with and without setting a LayoutAnimation. Tested that user interation during the animation is properly disabled.

![layout-anim-2](https://cloud.githubusercontent.com/assets/2677334/14760549/d60ebe2a-0914-11e6-8f17-ea04d8bf813b.gif)
Closes https://github.com/facebook/react-native/pull/7171

Differential Revision: D3352450

Pulled By: astreet

fbshipit-source-id: 233efa041626eb26d99511d12a924e54a10f96cc

ReactAndroid/src/main/java/com/facebook/react/uimanager/ViewGroupManager.java

@@ -48,6 +48,15 @@ public abstract class ViewGroupManager <T extends ViewGroup>
     parent.removeViewAt(index);
   }
 
+  public void removeView(T parent, View view) {
+    for (int i = 0; i < getChildCount(parent); i++) {
+      if (getChildAt(parent, i) == view) {
+        removeViewAt(parent, i);
+        break;
+      }
+    }
+  }
+
   public void removeAllViews(T parent) {
     for (int i = getChildCount(parent) - 1; i >= 0; i--) {
       removeViewAt(parent, i);