media: Reject pending CDM promise during destruction.

media/mojo/services/mojo_cdm_promise.cc

Index: media/mojo/services/mojo_cdm_promise.cc
diff --git a/media/mojo/services/mojo_cdm_promise.cc b/media/mojo/services/mojo_cdm_promise.cc
index 25131b2115a3bcb27f4baca3cdcb21c1fcb86e52..242fad70f2fe3ee8a173af9dee0809e43d2e8554 100644
--- a/media/mojo/services/mojo_cdm_promise.cc
+++ b/media/mojo/services/mojo_cdm_promise.cc
@@ -37,8 +37,13 @@ MojoCdmPromise<T...>::MojoCdmPromise(const CallbackType& callback)
 
 template <typename... T>
 MojoCdmPromise<T...>::~MojoCdmPromise() {
-  if (!callback_.is_null())
-    DVLOG(1) << "Promise not resolved before destruction.";
+  if (callback_.is_null())
+    return;
+
+  std::string message =

[ddorwin, 2016/02/25 19:14:12]

We have the same code in 4 places. Does it make sense to have a
RejectDueToDestruction() in the base class?

[xhwang, 2016/02/25 19:53:11]

reject() is virtual and we have to call the reject() in the subclasses. When we
are in the dtor of the base class it's already too late.

We can share the messages somehow but that doesn't really help too much.

+      "Unfulfilled promise rejected automatically during destruction.";
+  DVLOG(1) << message;
+  reject(MediaKeys::INVALID_STATE_ERROR, 0, message);
 }
 
 template <typename... T>