Use kRenderClientId command line flag when starting a render process

content/renderer/render_widget.h

Index: content/renderer/render_widget.h
diff --git a/content/renderer/render_widget.h b/content/renderer/render_widget.h
index 391ee08c8529bf4013c93c2332da883bc2bd647c..303ec6d4b9de43b9a6707d31eeb31a99bb85145d 100644
--- a/content/renderer/render_widget.h
+++ b/content/renderer/render_widget.h
@@ -20,6 +20,7 @@
 #include "base/observer_list.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
+#include "cc/surfaces/frame_sink_id.h"
 #include "content/common/content_export.h"
 #include "content/common/cursors/webcursor.h"
 #include "content/common/edit_command.h"
@@ -125,24 +126,26 @@ class CONTENT_EXPORT RenderWidget
   static RenderWidget* Create(int32_t opener_id,
                               CompositorDependencies* compositor_deps,
                               blink::WebPopupType popup_type,
-                              const ScreenInfo& screen_info);
+                              const ScreenInfo& screen_info,
+                              const cc::FrameSinkId& frame_sink_id);
 
   // Creates a new RenderWidget that will be attached to a RenderFrame.
   static RenderWidget* CreateForFrame(int routing_id,
                                       bool hidden,
                                       const ScreenInfo& screen_info,
                                       CompositorDependencies* compositor_deps,
-                                      blink::WebLocalFrame* frame);
+                                      blink::WebLocalFrame* frame,
+                                      const cc::FrameSinkId& frame_sink_id);
 
   // Used by content_layouttest_support to hook into the creation of
   // RenderWidgets.
-  using CreateRenderWidgetFunction =
-      RenderWidget* (*)(CompositorDependencies*,
-                        blink::WebPopupType,
-                        const ScreenInfo&,
-                        bool,
-                        bool,
-                        bool);
+  using CreateRenderWidgetFunction = RenderWidget* (*)(CompositorDependencies*,
+                                                       blink::WebPopupType,
+                                                       const ScreenInfo&,
+                                                       const cc::FrameSinkId&,
+                                                       bool,
+                                                       bool,
+                                                       bool);
   using RenderWidgetInitializedCallback = void (*)(RenderWidget*);
   static void InstallCreateHook(
       CreateRenderWidgetFunction create_render_widget,
@@ -390,6 +393,8 @@ class CONTENT_EXPORT RenderWidget
   // Indicates whether this widget has focus.
   bool has_focus() const { return has_focus_; }
 
+  const cc::FrameSinkId& frame_sink_id() const { return frame_sink_id_; }
+
   MouseLockDispatcher* mouse_lock_dispatcher() {
     return mouse_lock_dispatcher_.get();
   }
@@ -420,6 +425,7 @@ class CONTENT_EXPORT RenderWidget
   RenderWidget(CompositorDependencies* compositor_deps,
                blink::WebPopupType popup_type,
                const ScreenInfo& screen_info,
+               const cc::FrameSinkId& frame_sink_id,
                bool swapped_out,
                bool hidden,
                bool never_visible);
@@ -751,6 +757,8 @@ class CONTENT_EXPORT RenderWidget
   // |screen_info_| on some platforms, and defaults to 1 on other platforms.
   float device_scale_factor_;
 
+  cc::FrameSinkId frame_sink_id_;
+
   // The device color profile on supported platforms.
   std::vector<char> device_color_profile_;