MSE-in-Workers: Rename MediaSourceAttachmentImpl to SameThreadMediaSourceAttachment

As suggested in previous review [1], this change makes it more clear
that the concrete attachment being renamed here is the same-thread
version, since later changes will introduce a cross-thread version.

[1] https://chromium-review.googlesource.com/c/chromium/src/+/2380571/comment/7c8dd1e5_df26fa86/

BUG=878133

Change-Id: I74c8d1dce6f1d17095f8c71f84628c4a49c52413
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2388435
Commit-Queue: Matthew Wolenetz <wolenetz@chromium.org>
Reviewed-by: Will Cassella <cassew@google.com>
Cr-Commit-Position: refs/heads/master@{#803635}

third_party/blink/renderer/modules/mediasource/BUILD.gn

@@ -10,12 +10,12 @@ blink_modules_sources("mediasource") {
     "html_video_element_media_source.h",
     "media_source.cc",
     "media_source.h",
-    "media_source_attachment_impl.cc",
-    "media_source_attachment_impl.h",
     "media_source_registry_impl.cc",
     "media_source_registry_impl.h",
     "media_source_tracer_impl.cc",
     "media_source_tracer_impl.h",
+    "same_thread_media_source_attachment.cc",
+    "same_thread_media_source_attachment.h",
     "source_buffer.cc",
     "source_buffer.h",
     "source_buffer_list.cc",

third_party/blink/renderer/modules/mediasource/media_source_tracer_impl.h

@@ -16,9 +16,9 @@ class MediaSource;
 // Concrete MediaSourceTracer that enables an HTMLMediaElement and its attached
 // MediaSource on the same (main) thread to trace into each other. This enables
 // garbage collection to automatically detect and collect idle attachments of
-// these objects that have no other strong references.
-// A MediaSourceAttachmentImpl uses a MediaSourceTracerImpl as the authoritative
-// reference holder for each side of the attachment.
+// these objects that have no other strong references. Concrete
+// MediaSourceAttachments use MediaSourceTracerImpls as the authoritative
+// reference holders for each side of the attachments.
 class MediaSourceTracerImpl final : public MediaSourceTracer {
  public:
   MediaSourceTracerImpl(HTMLMediaElement* media_element,

third_party/blink/renderer/modules/mediasource/media_source_attachment_impl.cc → third_party/blink/renderer/modules/mediasource/same_thread_media_source_attachment.cc

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "third_party/blink/renderer/modules/mediasource/media_source_attachment_impl.h"
+#include "third_party/blink/renderer/modules/mediasource/same_thread_media_source_attachment.h"
 
 #include "third_party/blink/renderer/modules/mediasource/media_source.h"
 #include "third_party/blink/renderer/modules/mediasource/media_source_tracer_impl.h"
@@ -24,7 +24,8 @@ blink::MediaSource* GetMediaSource(blink::MediaSourceTracer* tracer) {
 
 namespace blink {
 
-MediaSourceAttachmentImpl::MediaSourceAttachmentImpl(MediaSource* media_source)
+SameThreadMediaSourceAttachment::SameThreadMediaSourceAttachment(
+    MediaSource* media_source)
     : registered_media_source_(media_source) {
   // This kind of attachment only operates on the main thread.
   DCHECK(IsMainThread());
@@ -36,9 +37,9 @@ MediaSourceAttachmentImpl::MediaSourceAttachmentImpl(MediaSource* media_source)
   DCHECK(HasOneRef());
 }
 
-MediaSourceAttachmentImpl::~MediaSourceAttachmentImpl() = default;
+SameThreadMediaSourceAttachment::~SameThreadMediaSourceAttachment() = default;
 
-void MediaSourceAttachmentImpl::Unregister() {
+void SameThreadMediaSourceAttachment::Unregister() {
   DVLOG(1) << __func__ << " this=" << this;
 
   // The only expected caller is a MediaSourceRegistryImpl on the main thread.
@@ -52,7 +53,8 @@ void MediaSourceAttachmentImpl::Unregister() {
   registered_media_source_ = nullptr;
 }
 
-MediaSourceTracer* MediaSourceAttachmentImpl::StartAttachingToMediaElement(
+MediaSourceTracer*
+SameThreadMediaSourceAttachment::StartAttachingToMediaElement(
     HTMLMediaElement* element) {
   if (!registered_media_source_)
     return nullptr;
@@ -60,42 +62,44 @@ MediaSourceTracer* MediaSourceAttachmentImpl::StartAttachingToMediaElement(
   return registered_media_source_->StartAttachingToMediaElement(element);
 }
 
-void MediaSourceAttachmentImpl::CompleteAttachingToMediaElement(
+void SameThreadMediaSourceAttachment::CompleteAttachingToMediaElement(
     MediaSourceTracer* tracer,
     std::unique_ptr<WebMediaSource> web_media_source) {
   GetMediaSource(tracer)->CompleteAttachingToMediaElement(
       std::move(web_media_source));
 }
 
-void MediaSourceAttachmentImpl::Close(MediaSourceTracer* tracer) {
+void SameThreadMediaSourceAttachment::Close(MediaSourceTracer* tracer) {
   GetMediaSource(tracer)->Close();
 }
 
-bool MediaSourceAttachmentImpl::IsClosed(MediaSourceTracer* tracer) const {
+bool SameThreadMediaSourceAttachment::IsClosed(
+    MediaSourceTracer* tracer) const {
   return GetMediaSource(tracer)->IsClosed();
 }
 
-double MediaSourceAttachmentImpl::duration(MediaSourceTracer* tracer) const {
+double SameThreadMediaSourceAttachment::duration(
+    MediaSourceTracer* tracer) const {
   return GetMediaSource(tracer)->duration();
 }
 
-WebTimeRanges MediaSourceAttachmentImpl::BufferedInternal(
+WebTimeRanges SameThreadMediaSourceAttachment::BufferedInternal(
     MediaSourceTracer* tracer) const {
   return GetMediaSource(tracer)->BufferedInternal();
 }
 
-WebTimeRanges MediaSourceAttachmentImpl::SeekableInternal(
+WebTimeRanges SameThreadMediaSourceAttachment::SeekableInternal(
     MediaSourceTracer* tracer) const {
   return GetMediaSource(tracer)->SeekableInternal();
 }
 
-TimeRanges* MediaSourceAttachmentImpl::Buffered(
+TimeRanges* SameThreadMediaSourceAttachment::Buffered(
     MediaSourceTracer* tracer) const {
   return GetMediaSource(tracer)->Buffered();
 }
 
-void MediaSourceAttachmentImpl::OnTrackChanged(MediaSourceTracer* tracer,
-                                               TrackBase* track) {
+void SameThreadMediaSourceAttachment::OnTrackChanged(MediaSourceTracer* tracer,
+                                                     TrackBase* track) {
   GetMediaSource(tracer)->OnTrackChanged(track);
 }
 

third_party/blink/renderer/modules/mediasource/media_source_attachment_impl.h → third_party/blink/renderer/modules/mediasource/same_thread_media_source_attachment.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_MEDIA_SOURCE_ATTACHMENT_IMPL_H_
-#define THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_MEDIA_SOURCE_ATTACHMENT_IMPL_H_
+#ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_SAME_THREAD_MEDIA_SOURCE_ATTACHMENT_H_
+#define THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_SAME_THREAD_MEDIA_SOURCE_ATTACHMENT_H_
 
 #include <memory>
 #include "third_party/blink/public/platform/web_time_range.h"
@@ -21,12 +21,12 @@ class TrackBase;
 class WebMediaSource;
 
 // Concrete attachment that supports operation only on the main thread.
-class MediaSourceAttachmentImpl final : public MediaSourceAttachment {
+class SameThreadMediaSourceAttachment final : public MediaSourceAttachment {
  public:
   // The only intended caller of this constructor is
   // URLMediaSource::createObjectUrl. The raw pointer is then adopted into a
-  // scoped_refptr in MediaSourceRegistryImpl::RegisterURL.
-  explicit MediaSourceAttachmentImpl(MediaSource* media_source);
+  // scoped_refptr in SameThreadMediaSourceRegistry::RegisterURL.
+  explicit SameThreadMediaSourceAttachment(MediaSource* media_source);
 
   void Unregister() override;
 
@@ -44,15 +44,15 @@ class MediaSourceAttachmentImpl final : public MediaSourceAttachment {
   void OnTrackChanged(MediaSourceTracer* tracer, TrackBase*) override;
 
  private:
-  ~MediaSourceAttachmentImpl() override;
+  ~SameThreadMediaSourceAttachment() override;
 
   // Cache of the registered MediaSource. Retains strong reference until
   // Unregister() is called.
   Persistent<MediaSource> registered_media_source_;
 
-  DISALLOW_COPY_AND_ASSIGN(MediaSourceAttachmentImpl);
+  DISALLOW_COPY_AND_ASSIGN(SameThreadMediaSourceAttachment);
 };
 
 }  // namespace blink
 
-#endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_MEDIA_SOURCE_ATTACHMENT_IMPL_H_
+#endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_MEDIASOURCE_SAME_THREAD_MEDIA_SOURCE_ATTACHMENT_H_

third_party/blink/renderer/modules/mediasource/url_media_source.cc

@@ -35,8 +35,8 @@
 #include "third_party/blink/renderer/core/html/media/media_source_attachment.h"
 #include "third_party/blink/renderer/core/url/dom_url.h"
 #include "third_party/blink/renderer/modules/mediasource/media_source.h"
-#include "third_party/blink/renderer/modules/mediasource/media_source_attachment_impl.h"
 #include "third_party/blink/renderer/modules/mediasource/media_source_registry_impl.h"
+#include "third_party/blink/renderer/modules/mediasource/same_thread_media_source_attachment.h"
 #include "third_party/blink/renderer/platform/bindings/script_state.h"
 #include "third_party/blink/renderer/platform/instrumentation/use_counter.h"
 
@@ -63,7 +63,8 @@ String URLMediaSource::createObjectURL(ScriptState* script_state,
   // further detail.
   // TODO(https://crbug.com/878133): Support creation of a cross-thread
   // attachment.
-  MediaSourceAttachment* attachment = new MediaSourceAttachmentImpl(source);
+  MediaSourceAttachment* attachment =
+      new SameThreadMediaSourceAttachment(source);
   DCHECK(attachment->HasOneRef());
 
   String url = DOMURL::CreatePublicURL(execution_context, attachment);