Improve docs

filter/featureBreaker/mc.go

 // 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.
 
 package featureBreaker
 
 import (
         "golang.org/x/net/context"
 
         mc "github.com/luci/gae/service/memcache"
@@ skipping 81 matching lines @@
         return
 }
 
 // FilterMC installs a counter mc filter in the context.
 func FilterMC(c context.Context, defaultError error) (context.Context, FeatureBreaker) {
         state := newState(defaultError)
         return mc.AddFilters(c, func(ic context.Context, rds mc.Interface) mc.Interface {
                 return &mcState{state, rds}
         }), state
 }