Replace source pointer in cc::CopyOutputRequest with a base::UnguessableToken

content/browser/renderer_host/render_widget_host_view_browsertest.cc

Index: content/browser/renderer_host/render_widget_host_view_browsertest.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_browsertest.cc b/content/browser/renderer_host/render_widget_host_view_browsertest.cc
index b2f1ae95e658638087625111b8507e7f8146426c..d9cdb1cc3675aa69d5084dcfddbb2df442673c71 100644
--- a/content/browser/renderer_host/render_widget_host_view_browsertest.cc
+++ b/content/browser/renderer_host/render_widget_host_view_browsertest.cc
@@ -250,9 +250,9 @@ class CompositingRenderWidgetHostViewBrowserTest
 class FakeFrameSubscriber : public RenderWidgetHostViewFrameSubscriber {
  public:
   FakeFrameSubscriber(
-    RenderWidgetHostViewFrameSubscriber::DeliverFrameCallback callback)
-      : callback_(callback) {
-  }
+      RenderWidgetHostViewFrameSubscriber::DeliverFrameCallback callback)
+      : callback_(callback),
+        source_id_for_copy_request_(base::UnguessableToken::Create()) {}
 
   bool ShouldCaptureFrame(const gfx::Rect& damage_rect,
                           base::TimeTicks present_time,
@@ -271,8 +271,13 @@ class FakeFrameSubscriber : public RenderWidgetHostViewFrameSubscriber {
     return true;
   }
 
+  const base::UnguessableToken& GetSourceIdForCopyRequest() override {
+    return source_id_for_copy_request_;
+  }
+
  private:
   DeliverFrameCallback callback_;
+  base::UnguessableToken source_id_for_copy_request_;
 };
 
 // Disable tests for Android as it has an incomplete implementation.