Reorganize net/disk_cache into backend specific directories.

net/disk_cache/blockfile/sparse_control.cc

Index: net/disk_cache/blockfile/sparse_control.cc
diff --git a/net/disk_cache/sparse_control.cc b/net/disk_cache/blockfile/sparse_control.cc
similarity index 99%
rename from net/disk_cache/sparse_control.cc
rename to net/disk_cache/blockfile/sparse_control.cc
index 1fd4fda46a8e18b8d948eaee222e9a1a95ab3dee..819d2873d1ac0015e676c2c104f6170e9922f78c 100644
--- a/net/disk_cache/sparse_control.cc
+++ b/net/disk_cache/blockfile/sparse_control.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "net/disk_cache/sparse_control.h"
+#include "net/disk_cache/blockfile/sparse_control.h"
 
 #include "base/bind.h"
 #include "base/format_macros.h"
@@ -13,9 +13,9 @@
 #include "base/time/time.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
-#include "net/disk_cache/backend_impl.h"
-#include "net/disk_cache/entry_impl.h"
-#include "net/disk_cache/file.h"
+#include "net/disk_cache/blockfile/backend_impl.h"
+#include "net/disk_cache/blockfile/entry_impl.h"
+#include "net/disk_cache/blockfile/file.h"
 #include "net/disk_cache/net_log_parameters.h"
 
 using base::Time;