Avoid casting non-content BadMessage codes to content BadMessage codes.

extensions/browser/bad_message.h

 // Copyright 2015 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 EXTENSIONS_BROWSER_BAD_MESSAGE_H_
 #define EXTENSIONS_BROWSER_BAD_MESSAGE_H_
 
 namespace content {
 class RenderProcessHost;
 }
 
 namespace extensions {
 namespace bad_message {
 
 // The browser process often chooses to terminate a renderer if it receives
 // a bad IPC message. The reasons are tracked for metrics.
 //
 // See also content/browser/bad_message.h.
 //
 // NOTE: Do not remove or reorder elements in this list. Add new entries at the

[Charlie Reis, 2016/08/10 21:09:50]

We haven't started using INVALID_ORIGIN yet as long as we land this in the same
canary.  We should remove it before it's too late.

 // end. Items may be renamed but do not change the values. We rely on the enum
 // values in histograms.
 enum BadMessageReason {
   EOG_BAD_ORIGIN = 0,
   EVG_BAD_ORIGIN = 1,
   BH_BLOB_NOT_OWNED = 2,
   EH_BAD_EVENT_ID = 3,
   AVG_BAD_INST_ID = 4,
   AVG_BAD_EXT_ID = 5,
   AVG_NULL_AVG = 6,
-  INVALID_ORIGIN = 7,
   // Please add new elements here. The naming convention is abbreviated class
   // name (e.g. ExtensionHost becomes EH) plus a unique description of the
   // reason. After making changes, you MUST update histograms.xml by running:
   // "python tools/metrics/histograms/update_bad_message_reasons.py"
   BAD_MESSAGE_MAX
 };
 
 // Called when the browser receives a bad IPC message from an extension process.
 // Logs the event, records a histogram metric for the |reason|, and terminates
 // the process for |host|.
 void ReceivedBadMessage(content::RenderProcessHost* host,
                         BadMessageReason reason);
 
 }  // namespace bad_message
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_BAD_MESSAGE_H_