Change back to destroy the CDM synchronously

third_party/WebKit/Source/modules/encryptedmedia/ContentDecryptionModuleResultPromise.cpp

Index: third_party/WebKit/Source/modules/encryptedmedia/ContentDecryptionModuleResultPromise.cpp
diff --git a/third_party/WebKit/Source/modules/encryptedmedia/ContentDecryptionModuleResultPromise.cpp b/third_party/WebKit/Source/modules/encryptedmedia/ContentDecryptionModuleResultPromise.cpp
index 931af86f682a01b8714233f05ce1538a017f9f55..ced2ce83b1474dd8f1b0a7b43a8208e655bb1843 100644
--- a/third_party/WebKit/Source/modules/encryptedmedia/ContentDecryptionModuleResultPromise.cpp
+++ b/third_party/WebKit/Source/modules/encryptedmedia/ContentDecryptionModuleResultPromise.cpp
@@ -7,6 +7,8 @@
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "core/dom/DOMException.h"
+#include "core/dom/ExecutionContext.h"
+#include "core/dom/ExecutionContextTask.h"
 #include "public/platform/WebString.h"
 #include "wtf/Assertions.h"
 
@@ -85,6 +87,18 @@ ScriptPromise ContentDecryptionModuleResultPromise::promise()
 
 void ContentDecryptionModuleResultPromise::reject(ExceptionCode code, const String& errorMessage)
 {
+    // Reject the promise asynchronously. This avoids problems when gc is
+    // destroying objects that result in unfulfilled promises being rejected.
+    // (Resolving promises is still done synchronously as there may be events
+    // already posted that need to happen only after the promise is resolved.)
+    // TODO(jrummell): Make resolving a promise asynchronous as well (including
+    // making sure events still happen after the promise is resolved).
+    getExecutionContext()->postTask(BLINK_FROM_HERE,
+        createSameThreadTask(&ContentDecryptionModuleResultPromise::rejectInternal, this, code, errorMessage));
+}
+
+void ContentDecryptionModuleResultPromise::rejectInternal(ExceptionCode code, const String& errorMessage)
+{
     m_resolver->reject(DOMException::create(code, errorMessage));
     m_resolver.clear();
 }