Update WEBGL_video_texture API

This patch adds the missing API in WEBGL_video_texture spec, renames
VideoElementTargetVideoTexture to shareVideoImageWEBGL, and corrects
the success logic in shareVideoImageWEBGL.

Bug: 776222
Change-Id: I17f2839dcef9c63346348c6d155e4eb6eb877760
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2194795
Commit-Queue: Shaobo Yan <shaobo.yan@intel.com>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#768557}

third_party/blink/renderer/modules/webgl/webgl_video_texture.cc

@@ -40,7 +40,7 @@ void WebGLVideoTexture::Trace(Visitor* visitor) {
   WebGLExtension::Trace(visitor);
 }
 
-VideoFrameMetadata* WebGLVideoTexture::VideoElementTargetVideoTexture(
+VideoFrameMetadata* WebGLVideoTexture::shareVideoImageWEBGL(
     ExecutionContext* execution_context,
     unsigned target,
     HTMLVideoElement* video,
@@ -90,10 +90,10 @@ VideoFrameMetadata* WebGLVideoTexture::VideoElementTargetVideoTexture(
 
   // TODO(shaobo.yan@intel.com) : A fallback path or exception needs to be
   // added when video is not using gpu decoder.
-  video->PrepareVideoFrameForWebGL(scoped.Context()->ContextGL(), target,
-                                   texture->Object(), already_uploaded_id,
-                                   frame_metadata_ptr);
-  if (!frame_metadata_ptr) {
+  bool success = video->PrepareVideoFrameForWebGL(
+      scoped.Context()->ContextGL(), target, texture->Object(),
+      already_uploaded_id, frame_metadata_ptr);
+  if (!success) {
     exception_state.ThrowTypeError("Failed to share video to texture.");
     return nullptr;
   }
@@ -125,4 +125,13 @@ VideoFrameMetadata* WebGLVideoTexture::VideoElementTargetVideoTexture(
 #endif  // defined OS_ANDROID
 }
 
+bool WebGLVideoTexture::releaseVideoImageWEBGL(
+    ExecutionContext* execution_context,
+    unsigned target,
+    ExceptionState& exception_state) {
+  // NOTE: In current WEBGL_video_texture status, there is no lock on video
+  // frame. So this API doesn't need to do anything.
+  return true;
+}
+
 }  // namespace blink

third_party/blink/renderer/modules/webgl/webgl_video_texture.h

@@ -27,11 +27,13 @@ class WebGLVideoTexture final : public WebGLExtension {
 
   // Get video frame from video frame compositor and bind it to platform
   // texture.
-  VideoFrameMetadata* VideoElementTargetVideoTexture(ExecutionContext*,
+  VideoFrameMetadata* shareVideoImageWEBGL(ExecutionContext*,
                                            unsigned,
                                            HTMLVideoElement*,
                                            ExceptionState&);
 
+  bool releaseVideoImageWEBGL(ExecutionContext*, unsigned, ExceptionState&);
+
  private:
   Member<VideoFrameMetadata> current_frame_metadata_;
 };

third_party/blink/renderer/modules/webgl/webgl_video_texture.idl

@@ -12,5 +12,6 @@
     const GLenum TEXTURE_VIDEO_IMAGE = 0x9248;
     const GLenum SAMPLER_VIDEO_IMAGE = 0x9249;
 
-    [CallWith=ExecutionContext, RaisesException] VideoFrameMetadata VideoElementTargetVideoTexture(GLenum target, HTMLVideoElement video);
+    [CallWith=ExecutionContext, RaisesException] VideoFrameMetadata shareVideoImageWEBGL(GLenum target, HTMLVideoElement video);
+    [CallWith=ExecutionContext, RaisesException] boolean releaseVideoImageWEBGL(GLenum target);
 };