Add layerTreeBuildHelper to control layer tree in ContentViewRenderView

content/browser/android/content_view_render_view.cc

Index: content/browser/android/content_view_render_view.cc
diff --git a/content/browser/android/content_view_render_view.cc b/content/browser/android/content_view_render_view.cc
index db42223b18ae88eeb2374d18bcb9818cfb76be2b..48a0ced469f7b7e1fd88d2733ffd8c1c0eaee317 100644
--- a/content/browser/android/content_view_render_view.cc
+++ b/content/browser/android/content_view_render_view.cc
@@ -38,18 +38,23 @@ ContentViewRenderView::ContentViewRenderView(JNIEnv* env,
       root_window_(root_window),
       current_surface_format_(0) {
   java_obj_.Reset(env, obj);
+  Java_ContentViewRenderView_setNativePtr(
+      env, obj, reinterpret_cast<intptr_t>(this));
 }
 
 ContentViewRenderView::~ContentViewRenderView() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  if (java_obj_.is_null())
+    return;
+
+  Java_ContentViewRenderView_clearNativePtr(env, java_obj_.obj());
 }
 
 // static
-static jlong Init(JNIEnv* env, jobject obj, jlong native_root_window) {
+static void Init(JNIEnv* env, jobject obj, jlong native_root_window) {
   gfx::NativeWindow root_window =
       reinterpret_cast<gfx::NativeWindow>(native_root_window);
-  ContentViewRenderView* content_view_render_view =
-      new ContentViewRenderView(env, obj, root_window);
-  return reinterpret_cast<intptr_t>(content_view_render_view);
+  new ContentViewRenderView(env, obj, root_window);
 }
 
 void ContentViewRenderView::Destroy(JNIEnv* env, jobject obj) {