cc: Do not report old query values when reused

cc/ThrottledTextureUploader.cpp

 // Copyright 2012 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 "config.h"
 #include "ThrottledTextureUploader.h"
 
 #include "Extensions3DChromium.h"
 #include <algorithm>
 #include <public/WebGraphicsContext3D.h>
@@ skipping 26 matching lines @@
     m_queryId = m_context->createQueryEXT();
 }
 
 ThrottledTextureUploader::Query::~Query()
 {
     m_context->deleteQueryEXT(m_queryId);
 }
 
 void ThrottledTextureUploader::Query::begin()
 {
+    m_hasValue = false;
     m_context->beginQueryEXT(Extensions3DChromium::COMMANDS_ISSUED_CHROMIUM, m_queryId);
 }
 
 void ThrottledTextureUploader::Query::end(double texturesUploaded)
 {
     m_context->endQueryEXT(Extensions3DChromium::COMMANDS_ISSUED_CHROMIUM);
     m_texturesUploaded = texturesUploaded;
 }
 
 bool ThrottledTextureUploader::Query::isPending()
@@ skipping 109 matching lines @@
 
         // Remove the oldest values from our history and insert the new one
         m_texturesPerSecondHistory.pop_back();
         m_texturesPerSecondHistory.push_front(texturesPerSecond);
 
         m_availableQueries.append(m_pendingQueries.takeFirst());
     }
 }
 
 }