Mojo-ify ShellViewHostMsg_LayoutDumpResponse.

content/shell/renderer/layout_test/layout_test_render_frame_observer.cc

Index: content/shell/renderer/layout_test/layout_test_render_frame_observer.cc
diff --git a/content/shell/renderer/layout_test/layout_test_render_frame_observer.cc b/content/shell/renderer/layout_test/layout_test_render_frame_observer.cc
index e10cca7d082a9e15798e75ad9e380c59db6ab7bf..e036cae8f9bf0cd36cede547cac012abb3eb7e47 100644
--- a/content/shell/renderer/layout_test/layout_test_render_frame_observer.cc
+++ b/content/shell/renderer/layout_test/layout_test_render_frame_observer.cc
@@ -44,13 +44,14 @@ void LayoutTestRenderFrameObserver::OnDestruct() {
   delete this;
 }
 
-void LayoutTestRenderFrameObserver::LayoutDumpRequest() {
+void LayoutTestRenderFrameObserver::DumpFrameLayout(
+    DumpFrameLayoutCallback callback) {
   std::string dump =
       LayoutTestRenderThreadObserver::GetInstance()
           ->test_interfaces()
           ->TestRunner()
           ->DumpLayout(render_frame()->GetWebFrame());
-  Send(new ShellViewHostMsg_LayoutDumpResponse(routing_id(), dump));
+  std::move(callback).Run(dump);
 }
 
 void LayoutTestRenderFrameObserver::ReplicateTestConfiguration(