Added UMA stats for extensions events on addListener.

tools/json_schema_compiler/schema_util.py

 # 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.
 """Utilies for the processing of schema python structures.
 """
 
 import json_parse
 
 def CapitalizeFirstLetter(value):
   return value[0].capitalize() + value[1:]
 
 def GetNamespace(ref):
   return SplitNamespace(ref)[0]
 
 def StripNamespace(ref):
   return SplitNamespace(ref)[1]
 
 def SplitNamespace(ref):
   """Returns (namespace, entity) from |ref|, e.g. app.window.AppWindow ->
   (app.window, AppWindow). If |ref| isn't qualified then returns (None, ref).
   """
   if '.' in ref:
     return tuple(ref.rsplit('.', 1))
   return (None, ref)
 
+def JsEventNameToHistogramValue(namespace_name, event_name):
+  """Transform a fully qualified event name like foo.bar.baz into FOO_BAR_BAZ
+
+  Format based on
+  chrome/browser/extensions/extension_event_histogram_value.h .
+
+  DOES NOT strip any leading 'experimental' prefix."""
+  full_name = namespace_name + "." + event_name
+  return full_name.upper().replace(".", "_")
+
 def JsFunctionNameToClassName(namespace_name, function_name):
   """Transform a fully qualified function name like foo.bar.baz into FooBarBaz
 
   Also strips any leading 'Experimental' prefix."""
   parts = []
   full_name = namespace_name + "." + function_name
   for part in full_name.split("."):
     parts.append(CapitalizeFirstLetter(part))
   if parts[0] == "Experimental":
     del parts[0]
   class_name = "".join(parts)
   return class_name