media: Add MediaPermission interface and MediaPermissionDispatcher.

media/blink/webencryptedmediaclient_impl.cc

 // 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.
 
 #include "webencryptedmediaclient_impl.h"
 
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "media/base/key_systems.h"
+#include "media/base/media_permission.h"
 #include "net/base/mime_util.h"
 #include "third_party/WebKit/public/platform/WebEncryptedMediaRequest.h"
 #include "third_party/WebKit/public/platform/WebMediaKeySystemConfiguration.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/platform/WebVector.h"
 #include "webcontentdecryptionmoduleaccess_impl.h"
 
 namespace media {
 
 static bool IsSupportedContentType(
@@ skipping 103 matching lines @@
   }
 
   // TODO(sandersd): Prompt for distinctive identifiers and/or persistent state
   // if required. Make sure that future checks are silent.
   // http://crbug.com/446263.
 
   return true;
 }
 
 WebEncryptedMediaClientImpl::WebEncryptedMediaClientImpl(
-    scoped_ptr<CdmFactory> cdm_factory)
-    : cdm_factory_(cdm_factory.Pass()) {
+    scoped_ptr<CdmFactory> cdm_factory,
+    MediaPermission* media_permission)
+    : cdm_factory_(cdm_factory.Pass()), media_permission_(media_permission) {
+  if (!media_permission_) {

[xhwang, 2015/01/26 21:49:06]

Need this to suppress a unused memeber variable warning/error on
|media_mermission_|.

FYI, |media_permission| could be null. See the change in html_document.cc.

[ddorwin, 2015/01/26 23:33:46]

Why not just an unused parameter macro? Or do you really want the logging?
Either way, the macro (with DVLOG_IF) would probably be better.
Are we going to need to check for null before calling? Should html_document.cc
provide a dummy impl instead?

[xhwang, 2015/01/27 00:01:58]

I remember we had that macro before, but I can't find it now.
DVLOG_IF doesn't work because it doesn't check the condition is release builds.
I debated about that. Allowing null seems to be simpler. 

Also, there's no permission code hooked up in HtmlViewer yet. So the dummy impl
would pretty much be NOTIMPLEMENTED() and I am not sure whether it should return
true or false. Currently HTMLViewer only supports clear key, so we actually
don't need permission check for now. How about revisiting this later when we add
more key system support and hook up permission service with HTMLViewer?

[ddorwin, 2015/01/27 00:09:03]

Perhaps we just remove parameters (this is a member) in that case. However, when
we need a parameter for a DCHECK, we apparently automatically handle the opt
build case:
https://code.google.com/p/chromium/codesearch#chromium/src/base/logging.h&q=u....
That may not apply to DLOG is not, though.
Ack

[xhwang, 2015/01/27 00:34:05]

Done.

However, when

+    DVLOG(2) << "Null |media_permission_|.";
+  }

[ddorwin, 2015/01/26 23:33:46]

TODO: Do something with the new pointer?

[xhwang, 2015/01/27 00:01:58]

Done.

 }
 
 WebEncryptedMediaClientImpl::~WebEncryptedMediaClientImpl() {
 }
 
 void WebEncryptedMediaClientImpl::requestMediaKeySystemAccess(
     blink::WebEncryptedMediaRequest request) {
   // TODO(jrummell): This should be asynchronous.
 
   // Continued from requestMediaKeySystemAccess(), step 7, from
@@ skipping 41 matching lines @@
       return;
     }
   }
 
   // 7.4 Reject promise with a new DOMException whose name is NotSupportedError.
   request.requestNotSupported(
       "None of the requested configurations were supported.");
 }
 
 }  // namespace media