Explicitly initialize secondary renderers for layout tests.

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 14bc812febfdf55e549325ee1603390ea91f7b2b..8638d3df10487f3a2e12ef7d23226307ded58ba7 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
@@ -38,6 +38,8 @@ bool LayoutTestRenderFrameObserver::OnMessageReceived(
                         OnReplicateTestConfiguration)
     IPC_MESSAGE_HANDLER(ShellViewMsg_SetTestConfiguration,
                         OnSetTestConfiguration)
+    IPC_MESSAGE_HANDLER(ShellViewMsg_SetupSecondaryRenderer,
+                        OnSetupSecondaryRenderer)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
 
@@ -66,8 +68,7 @@ void LayoutTestRenderFrameObserver::OnReplicateTestConfiguration(
     const ShellTestConfiguration& test_config,
     const base::DictionaryValue&
         accumulated_layout_test_runtime_flags_changes) {
-  LayoutTestRenderThreadObserver::GetInstance()
-      ->main_test_runner()
+  BlinkTestRunner::Get(render_frame()->GetRenderView())
       ->OnReplicateTestConfiguration(test_config);
 
   OnReplicateLayoutTestRuntimeFlagsChanges(
@@ -76,9 +77,13 @@ void LayoutTestRenderFrameObserver::OnReplicateTestConfiguration(
 
 void LayoutTestRenderFrameObserver::OnSetTestConfiguration(
     const ShellTestConfiguration& test_config) {
-  LayoutTestRenderThreadObserver::GetInstance()
-      ->main_test_runner()
+  BlinkTestRunner::Get(render_frame()->GetRenderView())
       ->OnSetTestConfiguration(test_config);
 }
 
+void LayoutTestRenderFrameObserver::OnSetupSecondaryRenderer() {
+  BlinkTestRunner::Get(render_frame()->GetRenderView())
+      ->OnSetupSecondaryRenderer();
+}
+
 }  // namespace content