media/gpu/test: Minor cleanup in video decoder tests.

This CL contains some minor cleanup in the video decoder tests:
- Update an outdated comment.
- Remove a duplicate define that's already defined in macros.h.
- Improved debug output when waiting for events.
- Moved some initialization to header file.

TEST=./video_decode_accelerator_tests on nocturne

BUG=None

Change-Id: Id0794cff6036396e46e293077663b62bba0b3560
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2032464Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Commit-Queue: David Staessens <dstaessens@chromium.org>
Cr-Commit-Position: refs/heads/master@{#742064}

media/gpu/test/video_player/video_decoder_client.h

@@ -64,12 +64,11 @@ class VideoDecoderClient {
   ~VideoDecoderClient();
 
   // Return an instance of the VideoDecoderClient. The
-  // |gpu_memory_buffer_factory|, |frame_renderer| and |frame_processors| will
-  // not be owned by the decoder client, the caller should guarantee they
-  // outlive the decoder client. The |event_cb| will be called whenever an event
-  // occurs (e.g. frame decoded) and should be thread-safe. Initialization is
-  // performed asynchronous, upon completion a 'kInitialized' event will be
-  // thrown.
+  // |gpu_memory_buffer_factory| will not be owned by the decoder client, the
+  // caller should guarantee it outlives the decoder client. The |event_cb| will
+  // be called whenever an event occurs (e.g. frame decoded) and should be
+  // thread-safe. Initialization is performed asynchronous, upon completion a
+  // 'kInitialized' event will be thrown.
   static std::unique_ptr<VideoDecoderClient> Create(
       const VideoPlayer::EventCallback& event_cb,
       gpu::GpuMemoryBufferFactory* gpu_memory_buffer_factory,

media/gpu/test/video_player/video_player.cc

@@ -10,8 +10,6 @@
 #include "media/gpu/test/video.h"
 #include "media/gpu/test/video_player/video_decoder_client.h"
 
-#define DVLOGF(level) DVLOG(level) << __func__ << "(): "
-
 namespace media {
 namespace test {
 
@@ -40,11 +38,7 @@ const char* EventName(VideoPlayerEvent event) {
 }  // namespace
 
 VideoPlayer::VideoPlayer()
-    : video_(nullptr),
-      video_player_state_(VideoPlayerState::kUninitialized),
-      event_cv_(&event_lock_),
-      video_player_event_counts_{},
-      event_id_(0) {}
+    : event_cv_(&event_lock_), video_player_event_counts_{}, event_id_(0) {}
 
 VideoPlayer::~VideoPlayer() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
@@ -188,7 +182,7 @@ FrameRenderer* VideoPlayer::GetFrameRenderer() const {
 bool VideoPlayer::WaitForEvent(VideoPlayerEvent event, size_t times) {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   DCHECK_GE(times, 1u);
-  DVLOGF(4) << "Event ID: " << static_cast<size_t>(event);
+  DVLOGF(4) << "Event: " << EventName(event);
 
   base::TimeDelta time_waiting;
   base::AutoLock auto_lock(event_lock_);

media/gpu/test/video_player/video_player.h

@@ -138,8 +138,8 @@ class VideoPlayer {
   // whether the decoder client should continue decoding frames.
   bool NotifyEvent(VideoPlayerEvent event);
 
-  const Video* video_;
-  VideoPlayerState video_player_state_;
+  const Video* video_ = nullptr;
+  VideoPlayerState video_player_state_ = VideoPlayerState::kUninitialized;
   std::unique_ptr<VideoDecoderClient> decoder_client_;
 
   // The timeout used when waiting for events.