Allow setContentDecryptionModule() to get called when setting is done.

content/renderer/media/webmediaplayer_impl.cc

 // Copyright 2013 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.
 
 #include "content/renderer/media/webmediaplayer_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <string>
 #include <vector>
@@ skipping 43 matching lines @@
 #include "media/filters/chunk_demuxer.h"
 #include "media/filters/ffmpeg_audio_decoder.h"
 #include "media/filters/ffmpeg_demuxer.h"
 #include "media/filters/ffmpeg_video_decoder.h"
 #include "media/filters/gpu_video_accelerator_factories.h"
 #include "media/filters/gpu_video_decoder.h"
 #include "media/filters/opus_audio_decoder.h"
 #include "media/filters/video_renderer_impl.h"
 #include "media/filters/vpx_video_decoder.h"
 #include "third_party/WebKit/public/platform/WebContentDecryptionModule.h"
+#include "third_party/WebKit/public/platform/WebContentDecryptionModuleResult.h"
 #include "third_party/WebKit/public/platform/WebMediaSource.h"
 #include "third_party/WebKit/public/platform/WebRect.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/platform/WebURL.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "third_party/WebKit/public/web/WebRuntimeFeatures.h"
 #include "third_party/WebKit/public/web/WebSecurityOrigin.h"
 #include "third_party/WebKit/public/web/WebView.h"
@@ skipping 702 matching lines @@
           BIND_TO_RENDER_LOOP(&WebMediaPlayerImpl::OnKeyError),
           BIND_TO_RENDER_LOOP(&WebMediaPlayerImpl::OnKeyMessage)));
     }
 
     GURL security_origin(frame_->document().securityOrigin().toString());
     if (!proxy_decryptor_->InitializeCDM(key_system, security_origin))
       return WebMediaPlayer::MediaKeyExceptionKeySystemNotSupported;
 
     if (proxy_decryptor_ && !decryptor_ready_cb_.is_null()) {
       base::ResetAndReturn(&decryptor_ready_cb_)
-          .Run(proxy_decryptor_->GetDecryptor());
+          .Run(proxy_decryptor_->GetDecryptor(), base::Closure());

[xhwang, 2014/07/29 20:58:07]

Here and below, use base::Bind(&base::DoNothing) instead of base::Closure() so
that we can assume |done_cb| is never null. Then we can drop the done_cb
checking in Decrypting* classes.

[jrummell, 2014/07/30 00:15:13]

Done.

     }
 
     current_key_system_ = key_system;
   } else if (key_system != current_key_system_) {
     return WebMediaPlayer::MediaKeyExceptionInvalidPlayerState;
   }
 
   std::string init_data_type = init_data_type_;
   if (init_data_type.empty())
     init_data_type = GuessInitDataType(init_data, init_data_length);
@@ skipping 84 matching lines @@
   if (current_key_system_.empty() || key_system != current_key_system_)
     return WebMediaPlayer::MediaKeyExceptionInvalidPlayerState;
 
   proxy_decryptor_->CancelKeyRequest(session_id);
   return WebMediaPlayer::MediaKeyExceptionNoError;
 }
 
 void WebMediaPlayerImpl::setContentDecryptionModule(
     blink::WebContentDecryptionModule* cdm) {
   DCHECK(main_loop_->BelongsToCurrentThread());
+  // TODO(jrummell): Remove this method once blink starts calling with 2
+  // parameters.
 
   // TODO(xhwang): Support setMediaKeys(0) if necessary: http://crbug.com/330324
   if (!cdm)
     return;
 
   web_cdm_ = ToWebContentDecryptionModuleImpl(cdm);
 
   if (web_cdm_ && !decryptor_ready_cb_.is_null())
-    base::ResetAndReturn(&decryptor_ready_cb_).Run(web_cdm_->GetDecryptor());
+    base::ResetAndReturn(&decryptor_ready_cb_)
+        .Run(web_cdm_->GetDecryptor(), base::Closure());
+}
+
+void WebMediaPlayerImpl::setContentDecryptionModule(
+    blink::WebContentDecryptionModule* cdm,
+    blink::WebContentDecryptionModuleResult result) {
+  DCHECK(main_loop_->BelongsToCurrentThread());
+
+  // TODO(xhwang): Support setMediaKeys(0) if necessary: http://crbug.com/330324
+  if (!cdm) {
+    result.completeWithError(
+        blink::WebContentDecryptionModuleExceptionNotSupportedError,
+        0,
+        "The existing MediaKeys object cannot be removed.");

[xhwang, 2014/07/29 20:58:07]

We may not have a CDM set yet. So more accurately this should be something like:
"Setting a null MediaKeys object not supported."

[jrummell, 2014/07/30 00:15:13]

Done.

+    return;
+  }
+
+  web_cdm_ = ToWebContentDecryptionModuleImpl(cdm);
+
+  if (web_cdm_ && !decryptor_ready_cb_.is_null()) {
+    base::ResetAndReturn(&decryptor_ready_cb_)
+        .Run(web_cdm_->GetDecryptor(),
+             BIND_TO_RENDER_LOOP1(
+                 &WebMediaPlayerImpl::ContentDecryptionModuleSet, result));
+  } else {
+    // No player, so setting CDM is complete.

[xhwang, 2014/07/29 20:58:07]

This is more of a spec question, so +ddorwin for comments.

This comment here let me feel a bit of inconsistency. If there's no player,
setting a CDM finishes immediately. If there is a player, setting a CDM will be
delayed until the playback resumes/starts. So setMeidaKeys + load is quite
different from load + setMediaKeys.

This will be more complicated on Chrome for Android because we send an IPC to
the browser to really "set" the CDM.

How about we remove "Attempt to Resume Playback If Necessary" as a condition to
resolve the promise? We still attempt to resume playback if necessary, but
that's not a necessary condition to resolve the promise.

If we do so, then we can simply return the promise after l.920. I might be
missing some important cases from JS's perspective though....

[ddorwin, 2014/07/30 22:41:34]

As I noted in the next PS, I'm not sure this comment is correct. Or at least
it's not obvious that the logic means "no player".

We don't need to successfully (re)start playback to resolve the promise, but the
pipeline and CDM must be successfully connected. In the no player case (handled
in Blink?), we can resolve immediately since there isn't a pipeline. load() (and
the subsequent pipeline initialization would use the CDM (make sure this is what
happens!) and fail if there are problems.

+    ContentDecryptionModuleSet(result);
+  }
+}
+
+void WebMediaPlayerImpl::ContentDecryptionModuleSet(
+    blink::WebContentDecryptionModuleResult result) {
+  result.complete();
 }
 
 void WebMediaPlayerImpl::InvalidateOnMainThread() {
   DCHECK(main_loop_->BelongsToCurrentThread());
   TRACE_EVENT0("media", "WebMediaPlayerImpl::InvalidateOnMainThread");
 
   client_->repaint();
 }
 
 void WebMediaPlayerImpl::OnPipelineSeeked(bool time_changed,
@@ skipping 398 matching lines @@
                  frame));
 }
 
 void WebMediaPlayerImpl::SetDecryptorReadyCB(
      const media::DecryptorReadyCB& decryptor_ready_cb) {
   DCHECK(main_loop_->BelongsToCurrentThread());
 
   // Cancels the previous decryptor request.
   if (decryptor_ready_cb.is_null()) {
     if (!decryptor_ready_cb_.is_null())
-      base::ResetAndReturn(&decryptor_ready_cb_).Run(NULL);
+      base::ResetAndReturn(&decryptor_ready_cb_).Run(NULL, base::Closure());
     return;
   }
 
   // TODO(xhwang): Support multiple decryptor notification request (e.g. from
   // video and audio). The current implementation is okay for the current
   // media pipeline since we initialize audio and video decoders in sequence.
   // But WebMediaPlayerImpl should not depend on media pipeline's implementation
   // detail.
   DCHECK(decryptor_ready_cb_.is_null());
 
   // Mixed use of prefixed and unprefixed EME APIs is disallowed by Blink.
   DCHECK(!proxy_decryptor_ || !web_cdm_);
 
   if (proxy_decryptor_) {
-    decryptor_ready_cb.Run(proxy_decryptor_->GetDecryptor());
+    decryptor_ready_cb.Run(proxy_decryptor_->GetDecryptor(), base::Closure());
     return;
   }
 
   if (web_cdm_) {
-    decryptor_ready_cb.Run(web_cdm_->GetDecryptor());
+    decryptor_ready_cb.Run(web_cdm_->GetDecryptor(), base::Closure());
     return;
   }
 
   decryptor_ready_cb_ = decryptor_ready_cb;
 }
 
 static void GetCurrentFrameAndSignal(
     VideoFrameCompositor* compositor,
     scoped_refptr<media::VideoFrame>* video_frame_out,
     base::WaitableEvent* event) {
@@ skipping 15 matching lines @@
   compositor_task_runner_->PostTask(FROM_HERE,
                                     base::Bind(&GetCurrentFrameAndSignal,
                                                base::Unretained(compositor_),
                                                &video_frame,
                                                &event));
   event.Wait();
   return video_frame;
 }
 
 }  // namespace content