Retry to add MockPresentationClient to use in layout tests.

content/shell/renderer/test_runner/web_test_proxy.cc

Index: content/shell/renderer/test_runner/web_test_proxy.cc
diff --git a/content/shell/renderer/test_runner/web_test_proxy.cc b/content/shell/renderer/test_runner/web_test_proxy.cc
index da62fc05f003e2c24df25866a0e3c31f7676eddf..c64d954ef96c0531d94d88e98d95d32252a449b3 100644
--- a/content/shell/renderer/test_runner/web_test_proxy.cc
+++ b/content/shell/renderer/test_runner/web_test_proxy.cc
@@ -18,6 +18,7 @@
 #include "content/shell/renderer/test_runner/event_sender.h"
 #include "content/shell/renderer/test_runner/mock_color_chooser.h"
 #include "content/shell/renderer/test_runner/mock_credential_manager_client.h"
+#include "content/shell/renderer/test_runner/mock_presentation_service.h"
 #include "content/shell/renderer/test_runner/mock_screen_orientation_client.h"
 #include "content/shell/renderer/test_runner/mock_web_speech_recognizer.h"
 #include "content/shell/renderer/test_runner/mock_web_user_media_client.h"
@@ -652,6 +653,12 @@ WebTestProxyBase::GetCredentialManagerClientMock() {
   return credential_manager_client_.get();
 }
 
+MockPresentationService* WebTestProxyBase::GetPresentationServiceMock() {
+  if (!presentation_service_.get())
+    presentation_service_.reset(new MockPresentationService());
+  return presentation_service_.get();
+}
+
 void WebTestProxyBase::ScheduleAnimation() {
   if (!test_interfaces_->GetTestRunner()->TestIsRunning())
     return;