avoid GCC content::CacheStorage::kSizeUnknown redeclaration error

content/browser/cache_storage/cache_storage_cache.cc

 // Copyright 2014 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 "content/browser/cache_storage/cache_storage_cache.h"
 
 #include <stddef.h>
 #include <algorithm>
 #include <limits>
 #include <memory>
@@ skipping 1172 matching lines @@
       &CacheStorageCache::UpdateCacheSizeGotSize,
       weak_ptr_factory_.GetWeakPtr(), base::Passed(CreateCacheHandle())));
 
   if (rv != net::ERR_IO_PENDING)
     UpdateCacheSizeGotSize(CreateCacheHandle(), rv);
 }
 
 void CacheStorageCache::UpdateCacheSizeGotSize(
     std::unique_ptr<CacheStorageCacheHandle> cache_handle,
     int current_cache_size) {
-  DCHECK_NE(current_cache_size, CacheStorage::kSizeUnknown);
+  DCHECK_NE(current_cache_size, kCacheStorageSizeUnknown);
   int64_t old_cache_size = cache_size_;
   cache_size_ = current_cache_size;
 
   int64_t size_delta = current_cache_size - old_cache_size;
 
   quota_manager_proxy_->NotifyStorageModified(
       storage::QuotaClient::kServiceWorkerCache, origin_,
       storage::kStorageTypeTemporary, size_delta);
 
   if (cache_observer_)
@@ skipping 179 matching lines @@
     InitGotCacheSize(callback, cache_create_error, rv);
 }
 
 void CacheStorageCache::InitGotCacheSize(const base::Closure& callback,
                                          CacheStorageError cache_create_error,
                                          int cache_size) {
   // Now that we know the cache size either 1) the cache size should be unknown
   // (which is why the size was calculated), or 2) it must match the current
   // size. If the sizes aren't equal then there is a bug in how the cache size
   // is saved in the store's index.
-  if (cache_size_ != CacheStorage::kSizeUnknown && cache_size_ != cache_size) {
+  if (cache_size_ != kCacheStorageSizeUnknown && cache_size_ != cache_size) {
     // TODO(cmumford): Add UMA for this.
     LOG(ERROR) << "Cache size/index mismatch";
     DCHECK_EQ(cache_size_, cache_size);
   }
   cache_size_ = cache_size;
   initializing_ = false;
   backend_state_ = (cache_create_error == CACHE_STORAGE_OK && backend_ &&
                     backend_state_ == BACKEND_UNINITIALIZED)
                        ? BACKEND_OPEN
                        : BACKEND_CLOSED;
@@ skipping 77 matching lines @@
       temp_entry, INDEX_RESPONSE_BODY, INDEX_SIDE_DATA);
   return blob_storage_context_->AddFinishedBlob(&blob_data);
 }
 
 std::unique_ptr<CacheStorageCacheHandle>
 CacheStorageCache::CreateCacheHandle() {
   return cache_storage_->CreateCacheHandle(this);
 }
 
 }  // namespace content