Add WebWidgetTestProxy.

components/test_runner/web_widget_test_client.h

Index: components/test_runner/web_widget_test_client.h
diff --git a/components/test_runner/web_widget_test_client.h b/components/test_runner/web_widget_test_client.h
index a5e9d5d1d1a87ccc23ba5a949fb7c8ce5bb93a5f..15113909abe7bb9a81386e56a1074380c695af83 100644
--- a/components/test_runner/web_widget_test_client.h
+++ b/components/test_runner/web_widget_test_client.h
@@ -18,6 +18,7 @@ namespace test_runner {
 class TestRunner;
 class WebTestDelegate;
 class WebViewTestProxyBase;
+class WebWidgetTestProxyBase;
 
 // WebWidgetTestClient implements WebWidgetClient interface, providing behavior
 // expected by tests.  WebWidgetTestClient ends up used by WebViewTestProxy
@@ -29,10 +30,15 @@ class WebWidgetTestClient : public blink::WebWidgetClient {
   // Caller has to ensure that all arguments (i.e. |test_runner| and |delegate|)
   // live longer than |this|.
   WebWidgetTestClient(TestRunner* test_runner,
-                      WebViewTestProxyBase* web_view_test_proxy_base);
+                      WebWidgetTestProxyBase* web_widget_test_proxy_base);
 
   virtual ~WebWidgetTestClient();
 
+  void set_web_view_test_proxy_base(
+      WebViewTestProxyBase* web_view_test_proxy_base) {
+    web_view_test_proxy_base_ = web_view_test_proxy_base;
+  }
+
   // WebWidgetClient overrides needed by WebViewTestProxy.
   blink::WebScreenInfo screenInfo() override;
   void scheduleAnimation() override;
@@ -49,6 +55,7 @@ class WebWidgetTestClient : public blink::WebWidgetClient {
   // Borrowed pointers to other parts of Layout Tests state.
   TestRunner* test_runner_;
   WebViewTestProxyBase* web_view_test_proxy_base_;
+  WebWidgetTestProxyBase* web_widget_test_proxy_base_;
 
   bool animation_scheduled_;