Clean up dependencies for disk_cache histogram_macros.h.

net/disk_cache/v3/entry_impl_v3.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 "net/disk_cache/v3/entry_impl_v3.h"
 
 #include "base/hash.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "net/disk_cache/bitmap.h"
 #include "net/disk_cache/cache_util.h"
 #include "net/disk_cache/net_log_parameters.h"
 #include "net/disk_cache/v3/backend_impl_v3.h"
 #include "net/disk_cache/v3/disk_format_v3.h"
+// #include "net/disk_cache/v3/sparse_control_v3.h"
+
+// Define BLOCKFILE_BACKEND_IMPL_OBJ to be a disk_cache::BackendImpl* in order
+// to use the CACHE_UMA histogram macro.
+#define BLOCKFILE_BACKEND_IMPL_OBJ backend_
 #include "net/disk_cache/v3/histogram_macros.h"
-// #include "net/disk_cache/v3/sparse_control_v3.h"
 
 using base::Time;
 using base::TimeDelta;
 using base::TimeTicks;
 
 namespace {
 
 const int kMaxBufferSize = 1024 * 1024;  // 1 MB.
 
 }  // namespace
@@ skipping 1422 matching lines @@
 
 int EntryImplV3::ReadyForSparseIO(const CompletionCallback& callback) {
   return net::ERR_FAILED;
 }
 
 EntryImplV3::~EntryImplV3() {
   NOTIMPLEMENTED();
 }
 
 }  // namespace disk_cache