MediaStream API: Update getUserMedia to match the spec

Source/modules/mediastream/NavigatorMediaStream.cpp

Index: Source/modules/mediastream/NavigatorMediaStream.cpp
diff --git a/Source/modules/mediastream/NavigatorMediaStream.cpp b/Source/modules/mediastream/NavigatorMediaStream.cpp
index 77870d6caa2166267c172e7e1c09496a6c104a86..78175436a2189154b3de47df7f6c969a2667e0a0 100644
--- a/Source/modules/mediastream/NavigatorMediaStream.cpp
+++ b/Source/modules/mediastream/NavigatorMediaStream.cpp
@@ -60,8 +60,7 @@ void NavigatorMediaStream::webkitGetUserMedia(Navigator& navigator, const Dictio
 
     RefPtr<UserMediaRequest> request = UserMediaRequest::create(navigator.frame()->document(), userMedia, options, successCallback, errorCallback, exceptionState);
     if (!request) {
-        if (!exceptionState.hadException())
-            exceptionState.throwDOMException(NotSupportedError, "Failed to request user media.");
+        ASSERT(exceptionState.hadException());
         return;
     }