Update MediaKeys interface for EME

content/renderer/media/webcontentdecryptionmoduleresult_helper.h

+// Copyright 2014 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.
+
+#ifndef CONTENT_RENDERER_MEDIA_WEBCONTENTDECRYPTIONMODULERESULT_HELPER_H_
+#define CONTENT_RENDERER_MEDIA_WEBCONTENTDECRYPTIONMODULERESULT_HELPER_H_
+
+#include <map>
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"

[ddorwin, 2014/09/23 18:57:31]

not used

[jrummell, 2014/09/23 22:36:35]

Done.

+#include "media/base/media_keys.h"

[ddorwin, 2014/09/23 18:57:31]

used?

[jrummell, 2014/09/23 22:36:35]

Needed for SimpleCdmPromise, NewSessionCdmPromise, etc.

+#include "third_party/WebKit/public/platform/WebContentDecryptionModuleResult.h"
+
+namespace content {
+
+typedef base::Callback<blink::WebContentDecryptionModuleResult::SessionStatus(
+    const std::string& web_session_id)> NewSessionCreatedCB;
+
+class WebContentDecryptionModuleResultHelper {
+ public:
+  // Take a copy of |result| and keep it around until needed. Returns a

[ddorwin, 2014/09/23 18:57:31]

s/Take/Make/

[ddorwin, 2014/09/23 18:57:31]

The copy is an impl detail. The first sentence should describe the primary
behavior. The copy should come later. Much of these descriptions are common.
Maybe there can be a general comment followed by specifics about the specific
Complete method that is called.

[jrummell, 2014/09/23 22:36:35]

Done.

[jrummell, 2014/09/23 22:36:35]

Done.

+  // SimpleCdmPromise that can be passed to the other methods to complete the
+  // WebContentDecryptionModuleResult. When SimpleCdmPromise is resolved,
+  // Complete() is called. If the SimpleCdmPromise is rejected,
+  // CompleteWithError() is called.
+  static scoped_ptr<media::SimpleCdmPromise> CreateSimpleCdmPromise(
+      blink::WebContentDecryptionModuleResult result);
+
+  // Returns a NewSessionCdmPromise that can be passed to the other methods to
+  // complete the WebContentDecryptionModuleResult. When NewSessionCdmPromise is
+  // resolved, |new_session_created_cb| is called, and then the return value
+  // passed to CompleteWithSession(). If the NewSessionCdmPromise is rejected,
+  // CompleteWithError() is called, and |new_session_created_cb| is not called.
+  // |uma_name| is the name of a CdmPromiseResult UMA, and is used to report
+  // the promise result (success or rejection code).
+  static scoped_ptr<media::NewSessionCdmPromise> CreateNewSessionCdmPromise(
+      blink::WebContentDecryptionModuleResult result,
+      const NewSessionCreatedCB& new_session_created_cb,

[ddorwin, 2014/09/23 18:57:31]

Is it a goal to eliminate this CB someday?

[jrummell, 2014/09/23 22:36:35]

Somebody has to decide if this is a new session, already existing session, or
not found (for load()). As well, now that the session_id is known (for
createSession()), a call needs to be made to the adapter to register it so that
events can reach the correct object.

+      std::string uma_name);

[ddorwin, 2014/09/23 18:57:31]

Why does only this one have a UMA? Do we not report UMAs for others?
From an API design perspective, these should all be consistent, even if we don't
currently pass uma names for all of them. In that case, you might swap the last
two parameters here.

[jrummell, 2014/09/23 22:36:35]

UMA is only done for CreateSession. However, all Create..Promise() methods take
|uma_name|.

+
+  // Take a copy of |result| and keep it around until needed. Returns a
+  // KeyIdsPromise that can be passed to the other methods to complete the
+  // WebContentDecryptionModuleResult. When KeyIdsPromise is resolved,
+  // CompleteWithKeyIds() is called. If the KeyIdsPromise is rejected,
+  // CompleteWithError() is called.
+  static scoped_ptr<media::KeyIdsPromise> CreateKeyIdsPromise(
+      blink::WebContentDecryptionModuleResult result);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(WebContentDecryptionModuleResultHelper);

[ddorwin, 2014/09/23 18:57:31]

DISALLOW_IMPLICIT_CONSTRUCTORS - it should never be instantiated.
(It's probably debatable whether it should be in a class.)

[jrummell, 2014/09/23 22:36:35]

Done.

+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_MEDIA_WEBCONTENTDECRYPTIONMODULERESULT_HELPER_H_