Convert DCHECK validating that |request_id| was found to a CHECK in SpeechRecognitionDispatcher.

content/renderer/speech_recognition_dispatcher.cc

Index: content/renderer/speech_recognition_dispatcher.cc
diff --git a/content/renderer/speech_recognition_dispatcher.cc b/content/renderer/speech_recognition_dispatcher.cc
index cb787359f73c5fb24549446ddaff1c45dd1f5ccc..0c433e33245f08df4f9618c3f77a5640da19a9a4 100644
--- a/content/renderer/speech_recognition_dispatcher.cc
+++ b/content/renderer/speech_recognition_dispatcher.cc
@@ -313,7 +313,7 @@ void SpeechRecognitionDispatcher::ResetAudioSink() {
 const WebSpeechRecognitionHandle& SpeechRecognitionDispatcher::GetHandleFromID(
     int request_id) {
   HandleMap::iterator iter = handle_map_.find(request_id);
-  DCHECK(iter != handle_map_.end());
+  CHECK(iter != handle_map_.end());
   return iter->second;
 }