Verify promise type before casting.

media/base/cdm_promise.cc

 // Copyright 2014 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 "media/base/cdm_promise.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 
@@ skipping 115 matching lines @@
   DCHECK(is_pending_);
   is_pending_ = false;
   if (!uma_name_.empty()) {
     base::LinearHistogram::FactoryGet(
         uma_name_, 1, NUM_RESULT_CODES, NUM_RESULT_CODES + 1,
         base::HistogramBase::kUmaTargetedHistogramFlag)->Add(SUCCESS);
   }
   resolve_cb_.Run();
 }
 
+CdmPromise::ResolveParameterType
+CdmPromiseTemplate<void>::GetResolveParameterType() const {
+  return VOID_TYPE;
+}
+
+template <>
+CdmPromise::ResolveParameterType
+CdmPromiseTemplate<std::string>::GetResolveParameterType() const {
+  return STRING_TYPE;
+}
+
+template <>
+CdmPromise::ResolveParameterType
+CdmPromiseTemplate<KeyIdsVector>::GetResolveParameterType() const {
+  return KEY_IDS_VECTOR_TYPE;
+}
+
 // Explicit template instantiation for the Promises needed.
 template class MEDIA_EXPORT CdmPromiseTemplate<std::string>;
 template class MEDIA_EXPORT CdmPromiseTemplate<KeyIdsVector>;
 
 }  // namespace media