Added MockPresentationClient to use in layout tests.

content/shell/renderer/test_runner/web_test_proxy.h

Index: content/shell/renderer/test_runner/web_test_proxy.h
diff --git a/content/shell/renderer/test_runner/web_test_proxy.h b/content/shell/renderer/test_runner/web_test_proxy.h
index e06d572380da806ae55af35642d6e5d74f8d2f99..018224eb88bbc6eda3eb1004813668ac38be9f72 100644
--- a/content/shell/renderer/test_runner/web_test_proxy.h
+++ b/content/shell/renderer/test_runner/web_test_proxy.h
@@ -76,6 +76,7 @@ typedef unsigned WebColor;
 namespace content {
 
 class MockCredentialManagerClient;
+class MockPresentationClient;
 class MockScreenOrientationClient;
 class MockWebSpeechRecognizer;
 class MockWebUserMediaClient;
@@ -131,6 +132,7 @@ class WebTestProxyBase {
   blink::WebMIDIClientMock* GetMIDIClientMock();
   MockWebSpeechRecognizer* GetSpeechRecognizerMock();
   MockCredentialManagerClient* GetCredentialManagerClientMock();
+  MockPresentationClient* GetPresentationClientMock();
 
   WebTaskList* mutable_task_list() { return &task_list_; }
 
@@ -267,6 +269,7 @@ class WebTestProxyBase {
   scoped_ptr<blink::WebMIDIClientMock> midi_client_;
   scoped_ptr<MockWebSpeechRecognizer> speech_recognizer_;
   scoped_ptr<MockScreenOrientationClient> screen_orientation_client_;
+  scoped_ptr<MockPresentationClient> presentation_client_;
 
   std::string accept_languages_;