Verify promise type before casting.

media/base/cdm_promise.cc

Index: media/base/cdm_promise.cc
diff --git a/media/base/cdm_promise.cc b/media/base/cdm_promise.cc
index 13ee760ad6caff189c8b38e50d5d74d3babe1c1c..74ff8bca68b1e93fc063e9b4fe1c63c45095f703 100644
--- a/media/base/cdm_promise.cc
+++ b/media/base/cdm_promise.cc
@@ -63,34 +63,66 @@ void CdmPromise::reject(MediaKeys::Exception exception_code,
   reject_cb_.Run(exception_code, system_code, error_message);
 }
 
-template <typename T>
-CdmPromiseTemplate<T>::CdmPromiseTemplate(
-    base::Callback<void(const T&)> resolve_cb,
+CdmPromiseTemplate<void>::CdmPromiseTemplate(base::Callback<void()> resolve_cb,
+                                             PromiseRejectedCB reject_cb)
+    : CdmPromise(reject_cb), resolve_cb_(resolve_cb) {
+  DCHECK(!resolve_cb_.is_null());
+}
+
+CdmPromiseTemplate<void>::CdmPromiseTemplate(base::Callback<void()> resolve_cb,
+                                             PromiseRejectedCB reject_cb,
+                                             const std::string& uma_name)
+    : CdmPromise(reject_cb, uma_name), resolve_cb_(resolve_cb) {
+  DCHECK(!resolve_cb_.is_null());
+  DCHECK(!uma_name_.empty());
+}
+
+CdmPromiseTemplate<void>::CdmPromiseTemplate() {
+}
+
+CdmPromiseTemplate<void>::~CdmPromiseTemplate() {
+  DCHECK(!is_pending_);
+}
+
+void CdmPromiseTemplate<void>::resolve() {
+  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;
+}
+
+CdmPromiseTemplate<std::string>::CdmPromiseTemplate(
+    base::Callback<void(const std::string&)> resolve_cb,
     PromiseRejectedCB reject_cb)
     : CdmPromise(reject_cb), resolve_cb_(resolve_cb) {
   DCHECK(!resolve_cb_.is_null());
 }
 
-template <typename T>
-CdmPromiseTemplate<T>::CdmPromiseTemplate(
-    base::Callback<void(const T&)> resolve_cb,
+CdmPromiseTemplate<std::string>::CdmPromiseTemplate(
+    base::Callback<void(const std::string&)> resolve_cb,
     PromiseRejectedCB reject_cb,
     const std::string& uma_name)
     : CdmPromise(reject_cb, uma_name), resolve_cb_(resolve_cb) {
   DCHECK(!resolve_cb_.is_null());
 }
 
-template <typename T>
-CdmPromiseTemplate<T>::CdmPromiseTemplate() {
+CdmPromiseTemplate<std::string>::CdmPromiseTemplate() {
 }
 
-template <typename T>
-CdmPromiseTemplate<T>::~CdmPromiseTemplate() {
+CdmPromiseTemplate<std::string>::~CdmPromiseTemplate() {
   DCHECK(!is_pending_);
 }
 
-template <typename T>
-void CdmPromiseTemplate<T>::resolve(const T& result) {
+void CdmPromiseTemplate<std::string>::resolve(const std::string& result) {
   DCHECK(is_pending_);
   is_pending_ = false;
   if (!uma_name_.empty()) {
@@ -101,28 +133,31 @@ void CdmPromiseTemplate<T>::resolve(const T& result) {
   resolve_cb_.Run(result);
 }
 
-CdmPromiseTemplate<void>::CdmPromiseTemplate(base::Callback<void()> resolve_cb,
-                                             PromiseRejectedCB reject_cb)
+CdmPromise::ResolveParameterType
+CdmPromiseTemplate<std::string>::GetResolveParameterType() const {
+  return STRING_TYPE;
+}
+
+CdmPromiseTemplate<KeyIdsVector>::CdmPromiseTemplate(
+    base::Callback<void(const KeyIdsVector&)> resolve_cb,
+    PromiseRejectedCB reject_cb)
     : CdmPromise(reject_cb), resolve_cb_(resolve_cb) {
   DCHECK(!resolve_cb_.is_null());
 }
 
-CdmPromiseTemplate<void>::CdmPromiseTemplate(base::Callback<void()> resolve_cb,
-                                             PromiseRejectedCB reject_cb,
-                                             const std::string& uma_name)
+CdmPromiseTemplate<KeyIdsVector>::CdmPromiseTemplate(
+    base::Callback<void(const KeyIdsVector&)> resolve_cb,
+    PromiseRejectedCB reject_cb,
+    const std::string& uma_name)
     : CdmPromise(reject_cb, uma_name), resolve_cb_(resolve_cb) {
   DCHECK(!resolve_cb_.is_null());
-  DCHECK(!uma_name_.empty());
 }
 
-CdmPromiseTemplate<void>::CdmPromiseTemplate() {
-}
-
-CdmPromiseTemplate<void>::~CdmPromiseTemplate() {
+CdmPromiseTemplate<KeyIdsVector>::~CdmPromiseTemplate() {
   DCHECK(!is_pending_);
 }
 
-void CdmPromiseTemplate<void>::resolve() {
+void CdmPromiseTemplate<KeyIdsVector>::resolve(const KeyIdsVector& result) {
   DCHECK(is_pending_);
   is_pending_ = false;
   if (!uma_name_.empty()) {
@@ -130,11 +165,12 @@ void CdmPromiseTemplate<void>::resolve() {
         uma_name_, 1, NUM_RESULT_CODES, NUM_RESULT_CODES + 1,
         base::HistogramBase::kUmaTargetedHistogramFlag)->Add(SUCCESS);
   }
-  resolve_cb_.Run();
+  resolve_cb_.Run(result);
 }
 
-// Explicit template instantiation for the Promises needed.
-template class MEDIA_EXPORT CdmPromiseTemplate<std::string>;
-template class MEDIA_EXPORT CdmPromiseTemplate<KeyIdsVector>;
+CdmPromise::ResolveParameterType
+CdmPromiseTemplate<KeyIdsVector>::GetResolveParameterType() const {
+  return KEY_IDS_VECTOR_TYPE;
+}
 
 }  // namespace media