Add PNACL_CACHE cache backend type, and allow larger files for this type.

net/disk_cache/histogram_macros.h

 // Copyright (c) 2011 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.
 
 // This file contains macros to simplify histogram reporting from the disk
 // cache. The main issue is that we want to have separate histograms for each
 // type of cache (regular vs. media, etc), without adding the complexity of
 // keeping track of a potentially large number of histogram objects that have to
 // survive the backend object that created them.
 
@@ skipping 97 matching lines @@
         break;\
       case net::MEDIA_CACHE:\
         CACHE_HISTOGRAM_##type(my_name.data(), sample);\
         break;\
       case net::APP_CACHE:\
         CACHE_HISTOGRAM_##type(my_name.data(), sample);\
         break;\
       case net::SHADER_CACHE:\
         CACHE_HISTOGRAM_##type(my_name.data(), sample);\
         break;\
+      case net::PNACL_CACHE:\
+        CACHE_HISTOGRAM_##type(my_name.data(), sample);\
+        break;\
       default:\
         NOTREACHED();\
         break;\
     }\
   }
 
 #endif  // NET_DISK_CACHE_HISTOGRAM_MACROS_H_