android webview: Keep zoom methods synchronous

content/browser/android/synchronous_compositor_host.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/android/synchronous_compositor_host.h"
 
 #include <utility>
 
 #include "base/containers/hash_tables.h"
 #include "base/memory/shared_memory.h"
@@ skipping 319 matching lines @@
 }
 
 void SynchronousCompositorHost::SetIsActive(bool is_active) {
   if (is_active_ == is_active)
     return;
   is_active_ = is_active;
   UpdateNeedsBeginFrames();
   SendAsyncCompositorStateIfNeeded();
 }
 
+void SynchronousCompositorHost::SynchronizeWithRenderer() {
+  SyncCompositorCommonBrowserParams common_browser_params;
+  PopulateCommonParams(&common_browser_params);
+  SyncCompositorCommonRendererParams common_renderer_params;
+  if (!sender_->Send(new SyncCompositorMsg_SynchronousUpdateState(
+          routing_id_, common_browser_params, &common_renderer_params))) {
+    return;
+  }
+  ProcessCommonParams(common_renderer_params);
+}
+
 void SynchronousCompositorHost::OnComputeScroll(
     base::TimeTicks animation_time) {
   if (!need_animate_scroll_)
     return;
   need_animate_scroll_ = false;
 
   SyncCompositorCommonBrowserParams common_browser_params;
   PopulateCommonParams(&common_browser_params);
   SyncCompositorCommonRendererParams common_renderer_params;
   sender_->Send(new SyncCompositorMsg_ComputeScroll(
@@ skipping 100 matching lines @@
         params.scrollable_size, params.page_scale_factor,
         params.min_page_scale_factor, params.max_page_scale_factor);
   }
 }
 
 void SynchronousCompositorHost::UpdateNeedsBeginFrames() {
   rwhva_->OnSetNeedsBeginFrames(is_active_ && need_begin_frame_);
 }
 
 }  // namespace content