AW: Remove unused sync_on_draw_hardware_ in RenderThreadManager

Bug: 
Change-Id: I39ab598aae721bdd8f88c0dd9b1668c45d7e0559
Reviewed-on: https://chromium-review.googlesource.com/727599Reviewed-by: Bo <boliu@chromium.org>
Commit-Queue: Bo <boliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#510138}

android_webview/browser/render_thread_manager.cc

@@ -12,10 +12,8 @@
 #include "android_webview/browser/hardware_renderer.h"
 #include "android_webview/browser/render_thread_manager_client.h"
 #include "android_webview/browser/scoped_app_gl_state_restore.h"
-#include "android_webview/common/aw_switches.h"
 #include "android_webview/public/browser/draw_gl.h"
 #include "base/bind.h"
-#include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/memory/ptr_util.h"
@@ -100,8 +98,6 @@ RenderThreadManager::RenderThreadManager(
       compositor_frame_producer_(nullptr),
       has_received_frame_(false),
       renderer_manager_key_(GLViewRendererManager::GetInstance()->NullKey()),
-      sync_on_draw_hardware_(base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kSyncOnDrawHardware)),
       inside_hardware_release_(false),
       weak_factory_on_ui_thread_(this) {
   DCHECK(ui_loop_->BelongsToCurrentThread());

android_webview/browser/render_thread_manager.h

@@ -115,7 +115,6 @@ class RenderThreadManager : public CompositorFrameConsumer {
   mutable base::Lock lock_;
   gfx::Vector2d scroll_offset_;
   ChildFrameQueue child_frames_;
-  const bool sync_on_draw_hardware_;
   bool inside_hardware_release_;
   ParentCompositorDrawConstraints parent_draw_constraints_;
   ReturnedResourcesMap returned_resources_map_;