'break' statement after 'return' is not required.

base/prefs/json_pref_store.cc

 // 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.
 
 #include "base/prefs/json_pref_store.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 42 matching lines @@
     const base::Value* value,
     const base::FilePath& path,
     int error_code,
     const std::string& error_msg) {
   if (!value) {
     DVLOG(1) << "Error while loading JSON file: " << error_msg
              << ", file: " << path.value();
     switch (error_code) {
       case JSONFileValueDeserializer::JSON_ACCESS_DENIED:
         return PersistentPrefStore::PREF_READ_ERROR_ACCESS_DENIED;
-        break;
       case JSONFileValueDeserializer::JSON_CANNOT_READ_FILE:
         return PersistentPrefStore::PREF_READ_ERROR_FILE_OTHER;
-        break;
       case JSONFileValueDeserializer::JSON_FILE_LOCKED:
         return PersistentPrefStore::PREF_READ_ERROR_FILE_LOCKED;
-        break;
       case JSONFileValueDeserializer::JSON_NO_SUCH_FILE:
         return PersistentPrefStore::PREF_READ_ERROR_NO_FILE;
-        break;
       default:
         // JSON errors indicate file corruption of some sort.
         // Since the file is corrupt, move it to the side and continue with
         // empty preferences.  This will result in them losing their settings.
         // We keep the old file for possible support and debugging assistance
         // as well as to detect if they're seeing these errors repeatedly.
         // TODO(erikkay) Instead, use the last known good file.
         base::FilePath bad = path.ReplaceExtension(kBadExtension);
 
         // If they've ever had a parse error before, put them in another bucket.
@@ skipping 447 matching lines @@
   DCHECK_EQ(31, num_buckets);
 
   // The histogram below is an expansion of the UMA_HISTOGRAM_CUSTOM_COUNTS
   // macro adapted to allow for a dynamically suffixed histogram name.
   // Note: The factory creates and owns the histogram.
   base::HistogramBase* histogram = base::Histogram::FactoryGet(
       histogram_name, min_value, max_value, num_buckets,
       base::HistogramBase::kUmaTargetedHistogramFlag);
   return histogram;
 }