Make base::Timer sequence-friendly.

media/base/android/media_codec_loop.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_ANDROID_MEDIA_CODEC_LOOP_H_
 #define MEDIA_BASE_ANDROID_MEDIA_CODEC_LOOP_H_
 
 #include <deque>
 #include <memory>
 #include <utility>
 #include <vector>
 
 #include "base/macros.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
+#include "base/single_thread_task_runner.h"
 #include "base/time/tick_clock.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "media/base/android/media_codec_bridge.h"
 #include "media/base/decode_status.h"
 #include "media/base/encryption_scheme.h"
 #include "media/base/media_export.h"
 #include "media/base/subsample_entry.h"
 
 // MediaCodecLoop is based on Android's MediaCodec API.
@@ skipping 69 matching lines @@
 //    (OnKeyAdded)
 //         |
 //      [Ready]
 //
 //     -[Any state]-
 //    |             |
 // (Flush ok) (Flush fails)
 //    |             |
 // [Ready]       [Error]
 
-namespace base {
-class SingleThreadTaskRunner;
-}
-
 namespace media {
 
 class MEDIA_EXPORT MediaCodecLoop {
  public:
   // TODO(liberato): this exists in video_decoder.h and audio_decoder.h too.
   using InitCB = base::Callback<void(bool success)>;
   using DecodeCB = base::Callback<void(DecodeStatus status)>;
 
   // Data that the client wants to put into an input buffer.
   struct InputData {
@@ skipping 79 matching lines @@
     virtual ~Client() {}
   };
 
   // We will take ownership of |media_codec|.  We will not destroy it until
   // we are destructed.  |media_codec| may not be null.
   // |sdk_level| is temporary.  It is used only to decouple MediaCodecLoop from
   // BuildInfo, until we get BuildInfo into a mockable state.
   MediaCodecLoop(int sdk_level,
                  Client* client,
                  std::unique_ptr<MediaCodecBridge> media_codec,
-                 scoped_refptr<base::SingleThreadTaskRunner> =
-                     scoped_refptr<base::SingleThreadTaskRunner>());
+                 scoped_refptr<base::SingleThreadTaskRunner> = nullptr);

[DaleCurtis, 2017/01/25 22:33:25]

Is the = nullptr even necessary? I didn't think there were a lot of callsites.

[gab, 2017/02/13 19:57:00]

Guess not, made mandatory.

   ~MediaCodecLoop();
 
   // Optionally set the tick clock used for testing.  It is our caller's
   // responsibility to maintain ownership of this, since
   // FakeSingleThreadTaskRunner maintains a raw ptr to it also.
   void SetTestTickClock(base::TickClock* test_tick_clock);
 
   // Does the MediaCodec processing cycle: enqueues an input buffer, then
   // dequeues output buffers.  This should be called by the client when more
   // work becomes available, such as when new input data arrives.  If codec
@@ skipping 103 matching lines @@
 
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<MediaCodecLoop> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaCodecLoop);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_ANDROID_MEDIA_CODEC_LOOP_H_