Move hash.h/cc from net/disk_cache to base.

net/disk_cache/storage_block-inl.h

 // 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.
 
 #ifndef NET_DISK_CACHE_STORAGE_BLOCK_INL_H_
 #define NET_DISK_CACHE_STORAGE_BLOCK_INL_H_
 
 #include "net/disk_cache/storage_block.h"
 
+#include "base/hash.h"
 #include "base/logging.h"
-#include "net/disk_cache/hash.h"
 #include "net/disk_cache/trace.h"
 
 namespace disk_cache {
 
 template<typename T> StorageBlock<T>::StorageBlock(MappedFile* file,
                                                    Addr address)
     : data_(NULL), file_(file), address_(address), modified_(false),
       own_data_(false), extended_(false) {
   if (address.num_blocks() > 1)
     extended_ = true;
@@ skipping 138 matching lines @@
       delete data_;
     } else {
       data_->~T();
       delete[] reinterpret_cast<char*>(data_);
     }
     own_data_ = false;
   }
 }
 
 template<typename T> uint32 StorageBlock<T>::CalculateHash() const {
-  return Hash(reinterpret_cast<char*>(data_), offsetof(T, self_hash));
+  return base::Hash(reinterpret_cast<char*>(data_), offsetof(T, self_hash));
 }
 
 }  // namespace disk_cache
 
 #endif  // NET_DISK_CACHE_STORAGE_BLOCK_INL_H_