[Media, Video] Update WMPI when the pipeline gets a new average keyframe distance.

media/filters/pipeline_controller_unittest.cc

Index: media/filters/pipeline_controller_unittest.cc
diff --git a/media/filters/pipeline_controller_unittest.cc b/media/filters/pipeline_controller_unittest.cc
index fe2f1585db6bca8e45fc645463942ec4b7e6a4a6..228014dc8c4c8438b2ccc26175ba3235cb5a7f03 100644
--- a/media/filters/pipeline_controller_unittest.cc
+++ b/media/filters/pipeline_controller_unittest.cc
@@ -136,6 +136,7 @@ class PipelineControllerTest : public ::testing::Test, public Pipeline::Client {
   void OnWaitingForDecryptionKey() override {}
   void OnVideoNaturalSizeChange(const gfx::Size& size) override {}
   void OnVideoOpacityChange(bool opaque) override {}
+  void OnVideoAverageKeyframeDistanceUpdate() override {}
 
   base::MessageLoop message_loop_;