Migrate encrypted media init callback.

This is a repeating callback because the field:
  EncryptedMediaInitDataCB encrypted_media_init_data_cb_
defined in:
  https://cs.chromium.org/chromium/src/media/filters/chunk_demuxer.h?rcl=44124afc1e06fad84a6e6df7b728f80c6de5b5ac&l=477
binds in:
  https://cs.chromium.org/chromium/src/media/filters/chunk_demuxer.cc?rcl=44124afc1e06fad84a6e6df7b728f80c6de5b5ac&l=674
against a base::RepeatingCallback declared in:
  https://cs.chromium.org/chromium/src/media/filters/source_buffer_state.cc?rcl=44124afc1e06fad84a6e6df7b728f80c6de5b5ac&l=152
to a type alias defined in:
  https://cs.chromium.org/chromium/src/media/base/stream_parser.h?rcl=44124afc1e06fad84a6e6df7b728f80c6de5b5ac&l=108

This is part of the base::Callback migration.

Context: https://cs.chromium.org/chromium/src/docs/callback.md?rcl=9fcc3764aea8f97e9f6de4a9ee61d554e67edcda&l=40

Bug: 714018
Change-Id: I393047264102bc9b847e6603f8e79913acd6d009
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2036062Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Auto-Submit: Jose Lopes <jabolopes@google.com>
Cr-Commit-Position: refs/heads/master@{#742776}

media/base/demuxer.h

@@ -57,8 +57,8 @@ class MEDIA_EXPORT Demuxer : public MediaResource {
   // First parameter - The type of initialization data.
   // Second parameter - The initialization data associated with the stream.
   using EncryptedMediaInitDataCB =
-      base::Callback<void(EmeInitDataType type,
-                          const std::vector<uint8_t>& init_data)>;
+      base::RepeatingCallback<void(EmeInitDataType type,
+                                   const std::vector<uint8_t>& init_data)>;
 
   // Notifies demuxer clients that media track configuration has been updated
   // (e.g. the initial stream metadata has been parsed successfully, or a new

media/blink/webmediaplayer_impl.cc

@@ -2686,7 +2686,7 @@ void WebMediaPlayerImpl::StartPipeline() {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
   Demuxer::EncryptedMediaInitDataCB encrypted_media_init_data_cb =
-      BindToCurrentLoop(base::Bind(
+      BindToCurrentLoop(base::BindRepeating(
           &WebMediaPlayerImpl::OnEncryptedMediaInitData, weak_this_));
 
   vfc_task_runner_->PostTask(

media/filters/chunk_demuxer.cc

@@ -447,14 +447,14 @@ void ChunkDemuxerStream::CompletePendingReadIfPossible_Locked() {
 ChunkDemuxer::ChunkDemuxer(
     const base::Closure& open_cb,
     const base::Closure& progress_cb,
-    const EncryptedMediaInitDataCB& encrypted_media_init_data_cb,
+    EncryptedMediaInitDataCB encrypted_media_init_data_cb,
     MediaLog* media_log)
     : state_(WAITING_FOR_INIT),
       cancel_next_seek_(false),
       host_(nullptr),
       open_cb_(open_cb),
       progress_cb_(progress_cb),
-      encrypted_media_init_data_cb_(encrypted_media_init_data_cb),
+      encrypted_media_init_data_cb_(std::move(encrypted_media_init_data_cb)),
       media_log_(media_log),
       duration_(kNoTimestamp),
       user_specified_duration_(-1),

media/filters/chunk_demuxer.h

@@ -207,7 +207,7 @@ class MEDIA_EXPORT ChunkDemuxer : public Demuxer {
   // |media_log| Used to report content and engine debug messages.
   ChunkDemuxer(const base::Closure& open_cb,
                const base::Closure& progress_cb,
-               const EncryptedMediaInitDataCB& encrypted_media_init_data_cb,
+               EncryptedMediaInitDataCB encrypted_media_init_data_cb,
                MediaLog* media_log);
   ~ChunkDemuxer() override;