CdmAdapter: Allow parallel SendPlatformChallenge() calls.

media/cdm/ppapi/cdm_adapter.h

Index: media/cdm/ppapi/cdm_adapter.h
diff --git a/media/cdm/ppapi/cdm_adapter.h b/media/cdm/ppapi/cdm_adapter.h
index cd65b181f07e224d97341c48db60294e5248bcab..0189c1fc353cdecf02014ceb9e09a864c88dc0f3 100644
--- a/media/cdm/ppapi/cdm_adapter.h
+++ b/media/cdm/ppapi/cdm_adapter.h
@@ -245,21 +245,21 @@ class CdmAdapter : public pp::Instance,
   void ReportOutputProtectionQuery();
   void ReportOutputProtectionQueryResult();
 
-  void SendPlatformChallengeDone(int32_t result);
+  struct PepperPlatformChallengeResponse {
+    pp::Var signed_data;
+    pp::Var signed_data_signature;
+    pp::Var platform_key_certificate;
+  };
+
+  void SendPlatformChallengeDone(
+      int32_t result,
+      const linked_ptr<PepperPlatformChallengeResponse>& response);
   void EnableProtectionDone(int32_t result);
   void QueryOutputProtectionStatusDone(int32_t result);
 
   pp::OutputProtection_Private output_protection_;
   pp::PlatformVerification platform_verification_;
 
-  // Since PPAPI doesn't provide handlers for CompletionCallbacks with more than
-  // one output we need to manage our own.  These values are only read by
-  // SendPlatformChallengeDone().
-  pp::Var signed_data_output_;
-  pp::Var signed_data_signature_output_;
-  pp::Var platform_key_certificate_output_;
-  bool challenge_in_progress_;
-
   // Same as above, these are only read by QueryOutputProtectionStatusDone().
   uint32_t output_link_mask_;
   uint32_t output_protection_mask_;