Rename MediaSource attachment methods (#3179)

The methods used to attach a MediaSource to an element do not currently
align with those used by Chromium. This change renames the methods to
have similar names to those used upstream.

* [Recent Chromium
methods](https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/modules/mediasource/media_source.h;l=118-131;drc=9ed4a90ee6aeaa3c1911d229dec6317d8fe8260d;bpv=0;bpt=0)
* [Relevant Chromium
commit](https://chromium-review.googlesource.com/c/chromium/src/+/2079384)

b/338426134

Change-Id: I0621a93c757d6df4dcb3ad64811707f7c933a13f

cobalt/dom/html_media_element.cc

@@ -866,7 +866,7 @@ void HTMLMediaElement::LoadResource(const GURL& initial_url,
       NoneSupported("Media source is NULL.");
       return;
     }
-    if (!media_source_->AttachToElement(this)) {
+    if (!media_source_->StartAttachingToMediaElement(this)) {
       media_source_ = nullptr;
       NoneSupported("Unable to attach media source.");
       return;
@@ -1643,7 +1643,7 @@ void HTMLMediaElement::SourceOpened(ChunkDemuxer* chunk_demuxer) {
   DCHECK(chunk_demuxer);
   BeginProcessingMediaPlayerCallback();
   DCHECK(media_source_);
-  media_source_->SetChunkDemuxerAndOpen(chunk_demuxer);
+  media_source_->CompleteAttachingToMediaElement(chunk_demuxer);
   EndProcessingMediaPlayerCallback();
 }
 

cobalt/dom/media_source.cc

@@ -399,7 +399,8 @@ bool MediaSource::IsTypeSupported(script::EnvironmentSettings* settings,
   }
 }
 
-bool MediaSource::AttachToElement(HTMLMediaElement* media_element) {
+bool MediaSource::StartAttachingToMediaElement(
+    HTMLMediaElement* media_element) {
   if (attached_element_) {
     return false;
   }
@@ -431,7 +432,7 @@ bool MediaSource::AttachToElement(HTMLMediaElement* media_element) {
   return true;
 }
 
-void MediaSource::SetChunkDemuxerAndOpen(ChunkDemuxer* chunk_demuxer) {
+void MediaSource::CompleteAttachingToMediaElement(ChunkDemuxer* chunk_demuxer) {
   DCHECK(chunk_demuxer);
   DCHECK(!chunk_demuxer_);
   DCHECK(attached_element_);

cobalt/dom/media_source.h

@@ -113,8 +113,8 @@ class MediaSource : public web::EventTarget {
   // Custom, not in any spec.
   //
   // HTMLMediaSource
-  bool AttachToElement(HTMLMediaElement* media_element);
-  void SetChunkDemuxerAndOpen(ChunkDemuxer* chunk_demuxer);
+  bool StartAttachingToMediaElement(HTMLMediaElement* media_element);
+  void CompleteAttachingToMediaElement(ChunkDemuxer* chunk_demuxer);
   void Close();
   bool IsClosed() const;
   scoped_refptr<TimeRanges> GetBufferedRange() const;