Keep lock during all of ScriptStreamer::fetchDataFromResourceBuffer.

Source/bindings/core/v8/ScriptStreamer.cpp

 // Copyright 2014 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 "bindings/core/v8/ScriptStreamer.h"
 
 #include "bindings/core/v8/ScriptStreamerThread.h"
 #include "bindings/core/v8/V8ScriptRunner.h"
 #include "core/dom/Document.h"
@@ skipping 270 matching lines @@
             SharedBuffer* buffer = streamer->resource()->resourceBuffer();
             m_resourceBuffer = RefPtr<SharedBuffer>(buffer);
         }
 
         fetchDataFromResourceBuffer(lengthOfBOM);
     }
 
     void fetchDataFromResourceBuffer(size_t lengthOfBOM)
     {
         ASSERT(isMainThread());
+        MutexLocker locker(m_mutex); // For m_cancelled + m_queueTailPosition.
 
         // Get as much data from the ResourceBuffer as we can.
         const char* data = 0;
         Vector<const char*> chunks;
         Vector<unsigned> chunkLengths;
         size_t dataLength = 0;
 
-        {
-            MutexLocker locker(m_mutex); // For m_cancelled + m_queueTailPosition.
-            if (!m_cancelled) {
-                while (unsigned length = m_resourceBuffer->getSomeData(data, m_queueTailPosition)) {
-                    // FIXME: Here we can limit based on the total length, if it turns
-                    // out that we don't want to give all the data we have (memory
-                    // vs. speed).
-                    chunks.append(data);
-                    chunkLengths.append(length);
-                    dataLength += length;
-                    m_queueTailPosition += length;
-                }
+        if (!m_cancelled) {
+            while (unsigned length = m_resourceBuffer->getSomeData(data, m_queueTailPosition)) {
+                // FIXME: Here we can limit based on the total length, if it turns
+                // out that we don't want to give all the data we have (memory
+                // vs. speed).
+                chunks.append(data);
+                chunkLengths.append(length);
+                dataLength += length;
+                m_queueTailPosition += length;
             }
         }
 
         // Copy the data chunks into a new buffer, since we're going to give the
         // data to a background thread.
         if (dataLength > lengthOfBOM) {
             dataLength -= lengthOfBOM;
             uint8_t* copiedData = new uint8_t[dataLength];
             unsigned offset = 0;
             for (size_t i = 0; i < chunks.size(); ++i) {
@@ skipping 322 matching lines @@
 
     // The Resource might go out of scope if the script is no longer
     // needed. This makes PendingScript notify the ScriptStreamer when it is
     // destroyed.
     script.setStreamer(ScriptStreamer::create(resource, scriptType, scriptState, compileOption));
 
     return true;
 }
 
 } // namespace blink