Remove VideoDecoder::PrepareForShutdownHack() and friends.

content/renderer/media/capture_video_decoder_unittest.cc

Index: content/renderer/media/capture_video_decoder_unittest.cc
diff --git a/content/renderer/media/capture_video_decoder_unittest.cc b/content/renderer/media/capture_video_decoder_unittest.cc
index f5b5f4ea5a627e5dd3bb0b3ddaf8fc6bcbc9e6ec..0f31a5a20b0d11ba437d8af52b3d19429dd9b80d 100644
--- a/content/renderer/media/capture_video_decoder_unittest.cc
+++ b/content/renderer/media/capture_video_decoder_unittest.cc
@@ -217,12 +217,12 @@ TEST_F(CaptureVideoDecoderTest, ReadAndShutdown) {
   // teardown the pipeline) even when there's no input frame.
   Initialize();
 
-  EXPECT_CALL(*this, FrameReady(media::VideoDecoder::kOk,
-                                HasSize(0, 0))).Times(2);
+  EXPECT_CALL(*this, FrameReady(media::VideoDecoder::kOk, HasSize(0, 0)));
   decoder_->Read(read_cb_);
-  decoder_->PrepareForShutdownHack();
+  Stop();
+
+  // Any read after stopping should be immediately satisfied.
+  EXPECT_CALL(*this, FrameReady(media::VideoDecoder::kOk, HasSize(0, 0)));
   decoder_->Read(read_cb_);
   message_loop_->RunAllPending();
-
-  Stop();
 }