Add an IPC to return the platform supported key-system names in Android.

components/cdm/browser/cdm_message_filter_android.h

Index: components/cdm/browser/cdm_message_filter_android.h
diff --git a/components/cdm/browser/cdm_message_filter_android.h b/components/cdm/browser/cdm_message_filter_android.h
index 47aa44507b430a3802896447a2c1334f9a410c19..538864829872695b3d18c9603b3b7ca5524fb740 100644
--- a/components/cdm/browser/cdm_message_filter_android.h
+++ b/components/cdm/browser/cdm_message_filter_android.h
@@ -29,10 +29,11 @@ class CdmMessageFilterAndroid
       const IPC::Message& message,
       content::BrowserThread::ID* thread) OVERRIDE;
 
-  // Retrieve the supported key systems.
-  void OnGetSupportedKeySystems(
-      const SupportedKeySystemRequest& request,
-      SupportedKeySystemResponse* response);
+  // Query the key system information.
+  void OnQueryKeySystemSupport(const SupportedKeySystemRequest& request,
+                               SupportedKeySystemResponse* response);
+
+  void OnGetPlatformKeySystemNames(std::vector<std::string>* key_systems);
 
   DISALLOW_COPY_AND_ASSIGN(CdmMessageFilterAndroid);
 };