Warn hackers that ResourceType is reported in histograms.

webkit/glue/resource_type.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 WEBKIT_GLUE_RESOURCE_TYPE_H__
 #define WEBKIT_GLUE_RESOURCE_TYPE_H__
 
 #include "base/basictypes.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebURLRequest.h"
 #include "webkit/glue/webkit_glue_export.h"
 
 class ResourceType {
  public:
+  // Used in histograms, so please add new types at the end, and rename unused
+  // entries to RESOURCETYPE_UNUSED_0, etc...
   enum Type {
     MAIN_FRAME = 0,  // top level page
     SUB_FRAME,       // frame or iframe
     STYLESHEET,      // a CSS stylesheet
     SCRIPT,          // an external script
     IMAGE,           // an image (jpg/gif/png/etc)
     FONT_RESOURCE,   // a font
     SUB_RESOURCE,    // an "other" subresource.
     OBJECT,          // an object (or embed) tag for a plugin,
                      // or a resource that a plugin requested.
@@ skipping 35 matching lines @@
            type == WORKER ||
            type == XHR;
   }
 
  private:
   // Don't instantiate this class.
   ResourceType();
   ~ResourceType();
 };
 #endif  // WEBKIT_GLUE_RESOURCE_TYPE_H__