android: Remove in-process sync compositor code path

android_webview/lib/main/aw_main_delegate.cc

 // Copyright (c) 2012 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 "android_webview/lib/main/aw_main_delegate.h"
 
 #include <memory>
 
 #include "android_webview/browser/aw_content_browser_client.h"
 #include "android_webview/browser/browser_view_renderer.h"
@@ skipping 54 matching lines @@
 
   BrowserViewRenderer::CalculateTileMemoryPolicy();
 
   // WebView apps can override WebView#computeScroll to achieve custom
   // scroll/fling. As a result, fling animations may not be ticked, potentially
   // confusing the tap suppression controller. Simply disable it for WebView.
   ui::GestureConfiguration::GetInstance()
       ->set_fling_touchscreen_tap_suppression_enabled(false);
 
   base::CommandLine* cl = base::CommandLine::ForCurrentProcess();
-  cl->AppendSwitch(switches::kIPCSyncCompositing);
   cl->AppendSwitch(cc::switches::kEnableBeginFrameScheduling);
 
   // WebView uses the Android system's scrollbars and overscroll glow.
   cl->AppendSwitch(switches::kDisableOverscrollEdgeEffect);
 
   // Pull-to-refresh should never be a default WebView action.
   cl->AppendSwitch(switches::kDisablePullToRefreshEffect);
 
   // Not yet supported in single-process mode.
   cl->AppendSwitch(switches::kDisableSharedWorkers);
@@ skipping 167 matching lines @@
 #if defined(VIDEO_HOLE)
 content::ExternalVideoSurfaceContainer*
 AwMainDelegate::CreateExternalVideoSurfaceContainer(
     content::WebContents* web_contents) {
   return external_video_surface::ExternalVideoSurfaceContainerImpl::Create(
       web_contents);
 }
 #endif
 
 }  // namespace android_webview