Expose receiveEvent as a high level API on UIManager

Summary:
This diff exposes receiveEvent on the UIManager class. This is necessary to support backward compatibility between Fabric and classic RN

changelog: [Internal]

Reviewed By: JoshuaGross

Differential Revision: D21979687

fbshipit-source-id: 1ec75896687d55e699f79c520e21f05fac368ee6

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

@@ -950,4 +950,11 @@ public class UIManagerModule extends ReactContextBaseJavaModule
         .getNativeViewHierarchyManager()
         .resolveView(tag);
   }
+
+  @Override
+  public void receiveEvent(int targetTag, String eventName, @Nullable WritableMap event) {
+    getReactApplicationContext()
+        .getJSModule(RCTEventEmitter.class)
+        .receiveEvent(targetTag, eventName, event);
+  }
 }