media: CdmFactory creates CDM (MediaKeys) asynchronously.

content/renderer/media/crypto/render_cdm_factory.cc

Index: content/renderer/media/crypto/render_cdm_factory.cc
diff --git a/content/renderer/media/crypto/render_cdm_factory.cc b/content/renderer/media/crypto/render_cdm_factory.cc
index c871f9c2d551ae31e2be7e06ffcb2579b8c61853..23c335ff59759813b0cd89640ed60eae09541e4e 100644
--- a/content/renderer/media/crypto/render_cdm_factory.cc
+++ b/content/renderer/media/crypto/render_cdm_factory.cc
@@ -4,11 +4,13 @@
 
 #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)
@@ -37,7 +39,7 @@ 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,
@@ -46,38 +48,45 @@ scoped_ptr<media::MediaKeys> RenderCdmFactory::Create(
     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;
+  scoped_ptr<media::MediaKeys> cdm;
+
+  if (!security_origin.is_valid()) {
+    base::MessageLoopProxy::current()->PostTask(
+        FROM_HERE, base::Bind(cdm_created_cb, base::Passed(&cdm)));

[ddorwin, 2015/04/10 00:59:43]

nit: Does nullptr not work here? (It's a bit weird to pass a real value even
though we can see it's invalid above. Also, there is an (unlikely)  refactoring
risk.)

[xhwang, 2015/04/10 17:41:17]

Done.

+    return;
+  }
 
   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)
-  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));
+    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);
-  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;
+    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)
+  }
+
+  base::MessageLoopProxy::current()->PostTask(
+      FROM_HERE, base::Bind(cdm_created_cb, base::Passed(&cdm)));
 }
 
 }  // namespace content