Fix a potential assert in SpeechRecognizer dtor.

chrome/browser/speech/speech_recognizer.cc

 // Copyright (c) 2010 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 "chrome/browser/speech/speech_recognizer.h"
 
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
 #include "base/time.h"
 #include "chrome/browser/browser_thread.h"
@@ skipping 111 matching lines @@
   VLOG(1) << "SpeechRecognizer stopping record.";
   audio_controller_->Close();
   audio_controller_ = NULL;  // Releases the ref ptr.
   encoder_->Flush();
 
   delegate_->DidCompleteRecording(caller_id_);
 
   // Since the http request takes a single string as POST data, allocate
   // one and copy over bytes from the audio buffers to the string.
   // And If we haven't got any audio yet end the recognition sequence here.
+  string mime_type = encoder_->mime_type();
   string data;
-  if (!encoder_->GetEncodedData(&data)) {
+  encoder_->GetEncodedData(&data);
+  encoder_.reset();
+
+  if (data.empty()) {
     // Guard against the delegate freeing us until we finish our job.
     scoped_refptr<SpeechRecognizer> me(this);
     delegate_->DidCompleteRecognition(caller_id_);
   } else {
     DCHECK(!request_.get());
     request_.reset(new SpeechRecognitionRequest(
         Profile::GetDefaultRequestContext(), this));
     request_->Send(language_, grammar_, hardware_info_, origin_url_,
-                   encoder_->mime_type(), data);
+                   mime_type, data);
   }
-  encoder_.reset();
 }
 
 void SpeechRecognizer::ReleaseAudioBuffers() {
 }
 
 // Invoked in the audio thread.
 void SpeechRecognizer::OnError(AudioInputController* controller,
                                int error_code) {
   BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
                          NewRunnableMethod(this,
@@ skipping 97 matching lines @@
 
 void SpeechRecognizer::InformErrorAndCancelRecognition(ErrorCode error) {
   CancelRecognition();
 
   // Guard against the delegate freeing us until we finish our job.
   scoped_refptr<SpeechRecognizer> me(this);
   delegate_->OnRecognizerError(caller_id_, error);
 }
 
 }  // namespace speech_input