[android_webview] Fix use after free in intercepted requests.

android_webview/browser/input_stream.h

 // Copyright (c) 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.
 
 #ifndef ANDROID_WEBVIEW_BROWSER_INPUT_STREAM_H_
 #define ANDROID_WEBVIEW_BROWSER_INPUT_STREAM_H_
 
 #include "base/basictypes.h"
 
 namespace net {
 class IOBuffer;
 }
 
 namespace android_webview {
 
 // Abstract wrapper used to access the InputStream Java class.
+// This class is safe to pass around between threads (the destructor,
+// constructor and methods can be called on different threads) but calling
+// methods concurrently might have undefined results.
 class InputStream {
  public:
   virtual ~InputStream() {}
 
   // Sets |bytes_available| to the number of bytes that can be read (or skipped
   // over) from this input stream without blocking by the next caller of a
   // method for this input stream.
   // Returns true if completed successfully or false if an exception was
   // thrown.
   virtual bool BytesAvailable(int* bytes_available) const = 0;
@@ skipping 12 matching lines @@
   // thrown.
   virtual bool Read(net::IOBuffer* dest, int length, int* bytes_read) = 0;
 
  protected:
   InputStream() {}
 };
 
 } // namespace android_webview
 
 #endif //  ANDROID_WEBVIEW_BROWSER_INPUT_STREAM_H_