media: CdmFactory creates CDM (MediaKeys) asynchronously.

content/renderer/media/crypto/render_cdm_factory.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/crypto/render_cdm_factory.h"
 
+#include "base/bind.h"
+#include "base/location.h"
 #include "base/logging.h"
+#include "base/message_loop/message_loop_proxy.h"
 #include "media/base/key_systems.h"
 #include "media/cdm/aes_decryptor.h"
 #include "url/gurl.h"
-
 #if defined(ENABLE_PEPPER_CDMS)
 #include "content/renderer/media/crypto/ppapi_decryptor.h"
 #elif defined(ENABLE_BROWSER_CDMS)
 #include "content/renderer/media/crypto/proxy_media_keys.h"
 #endif  // defined(ENABLE_PEPPER_CDMS)
 
 namespace content {
 
 RenderCdmFactory::RenderCdmFactory(
 #if defined(ENABLE_PEPPER_CDMS)
     const CreatePepperCdmCB& create_pepper_cdm_cb,
 #elif defined(ENABLE_BROWSER_CDMS)
     RendererCdmManager* manager,
 #endif  // defined(ENABLE_PEPPER_CDMS)
     RenderFrame* render_frame)
     : RenderFrameObserver(render_frame)
 #if defined(ENABLE_PEPPER_CDMS)
     , create_pepper_cdm_cb_(create_pepper_cdm_cb)
 #elif defined(ENABLE_BROWSER_CDMS)
     , manager_(manager)
 #endif  // defined(ENABLE_PEPPER_CDMS)
 {
 }
 
 RenderCdmFactory::~RenderCdmFactory() {
   DCHECK(thread_checker_.CalledOnValidThread());
 }
 
-scoped_ptr<media::MediaKeys> RenderCdmFactory::Create(
+void RenderCdmFactory::Create(
     const std::string& key_system,
     bool allow_distinctive_identifier,
     bool allow_persistent_state,
     const GURL& security_origin,
     const media::SessionMessageCB& session_message_cb,
     const media::SessionClosedCB& session_closed_cb,
     const media::LegacySessionErrorCB& legacy_session_error_cb,
     const media::SessionKeysChangeCB& session_keys_change_cb,
-    const media::SessionExpirationUpdateCB& session_expiration_update_cb) {
+    const media::SessionExpirationUpdateCB& session_expiration_update_cb,
+    const CdmCreatedCB& cdm_created_cb) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
-  if (!security_origin.is_valid())
-    return nullptr;
+  if (!security_origin.is_valid()) {
+    base::MessageLoopProxy::current()->PostTask(
+        FROM_HERE, base::Bind(cdm_created_cb, nullptr));
+    return;
+  }
+
+  scoped_ptr<media::MediaKeys> cdm;
 
   if (media::CanUseAesDecryptor(key_system)) {
     // TODO(sandersd): Currently the prefixed API always allows distinctive
     // identifiers and persistent state. Once that changes we can sanity check
     // here that neither is allowed for AesDecryptor, since it does not support
     // them and should never be configured that way. http://crbug.com/455271
-    return scoped_ptr<media::MediaKeys>(
-        new media::AesDecryptor(security_origin, session_message_cb,
-                                session_closed_cb, session_keys_change_cb));
+    cdm.reset(new media::AesDecryptor(security_origin, session_message_cb,
+                                      session_closed_cb,
+                                      session_keys_change_cb));
+  } else {
+#if defined(ENABLE_PEPPER_CDMS)
+    cdm = PpapiDecryptor::Create(
+        key_system, allow_distinctive_identifier, allow_persistent_state,
+        security_origin, create_pepper_cdm_cb_, session_message_cb,
+        session_closed_cb, legacy_session_error_cb, session_keys_change_cb,
+        session_expiration_update_cb);
+#elif defined(ENABLE_BROWSER_CDMS)
+    DCHECK(allow_distinctive_identifier);
+    DCHECK(allow_persistent_state);
+    cdm = ProxyMediaKeys::Create(
+        key_system, security_origin, manager_, session_message_cb,
+        session_closed_cb, legacy_session_error_cb, session_keys_change_cb,
+        session_expiration_update_cb);
+#endif  // defined(ENABLE_PEPPER_CDMS)
   }
 
-#if defined(ENABLE_PEPPER_CDMS)
-  return scoped_ptr<media::MediaKeys>(PpapiDecryptor::Create(
-      key_system, allow_distinctive_identifier, allow_persistent_state,
-      security_origin, create_pepper_cdm_cb_, session_message_cb,
-      session_closed_cb, legacy_session_error_cb, session_keys_change_cb,
-      session_expiration_update_cb));
-#elif defined(ENABLE_BROWSER_CDMS)
-  DCHECK(allow_distinctive_identifier);
-  DCHECK(allow_persistent_state);
-  return scoped_ptr<media::MediaKeys>(ProxyMediaKeys::Create(
-      key_system, security_origin, manager_, session_message_cb,
-      session_closed_cb, legacy_session_error_cb, session_keys_change_cb,
-      session_expiration_update_cb));
-#else
-  return nullptr;
-#endif  // defined(ENABLE_PEPPER_CDMS)
+  base::MessageLoopProxy::current()->PostTask(
+      FROM_HERE, base::Bind(cdm_created_cb, base::Passed(&cdm)));
 }
 
 }  // namespace content