Fence on draws that are reported

Change-Id: Ib2ec16cbda40f40df1710bdc868869ea8301f17e
diff --git a/core/jni/android_view_ThreadedRenderer.cpp b/core/jni/android_view_ThreadedRenderer.cpp
index 98bec1b..32890cf 100644
--- a/core/jni/android_view_ThreadedRenderer.cpp
+++ b/core/jni/android_view_ThreadedRenderer.cpp
@@ -182,6 +182,12 @@
     proxy->destroyLayer(layer);
 }
 
+static void android_view_ThreadedRenderer_fence(JNIEnv* env, jobject clazz,
+        jlong proxyPtr) {
+    RenderProxy* proxy = reinterpret_cast<RenderProxy*>(proxyPtr);
+    proxy->fence();
+}
+
 #endif
 
 // ----------------------------------------------------------------------------
@@ -209,6 +215,7 @@
     { "nCreateTextureLayer", "(J)J", (void*) android_view_ThreadedRenderer_createTextureLayer },
     { "nCopyLayerInto", "(JJJ)Z", (void*) android_view_ThreadedRenderer_copyLayerInto },
     { "nDestroyLayer", "(JJ)V", (void*) android_view_ThreadedRenderer_destroyLayer },
+    { "nFence", "(J)V", (void*) android_view_ThreadedRenderer_fence },
 #endif
 };