Hide console log messages for imported WPT tests

content/shell/renderer/layout_test/blink_test_runner.h

Index: content/shell/renderer/layout_test/blink_test_runner.h
diff --git a/content/shell/renderer/layout_test/blink_test_runner.h b/content/shell/renderer/layout_test/blink_test_runner.h
index 1d44f4ecaa42fbfbf28c6b0baff1a0ce28030e65..a373dc185d64c3f463c3d9ea14c393d92dcb3d74 100644
--- a/content/shell/renderer/layout_test/blink_test_runner.h
+++ b/content/shell/renderer/layout_test/blink_test_runner.h
@@ -72,6 +72,7 @@ class BlinkTestRunner : public RenderViewObserver,
   void SetDeviceMotionData(const blink::WebDeviceMotionData& data) override;
   void SetDeviceOrientationData(
       const blink::WebDeviceOrientationData& data) override;
+  void PrintStderrMessage(const std::string& message) override;
   void PrintMessage(const std::string& message) override;
   void PostTask(const base::Closure& task) override;
   void PostDelayedTask(const base::Closure& task, long long ms) override;