Reorganize net/disk_cache into backend specific directories.

net/disk_cache/blockfile/in_flight_backend_io.cc

Index: net/disk_cache/blockfile/in_flight_backend_io.cc
diff --git a/net/disk_cache/in_flight_backend_io.cc b/net/disk_cache/blockfile/in_flight_backend_io.cc
similarity index 98%
rename from net/disk_cache/in_flight_backend_io.cc
rename to net/disk_cache/blockfile/in_flight_backend_io.cc
index 394cc8515d07519a417832d784649f1d0846022b..c9df6808b3583a68220d17cb94db0c16d0e00ca8 100644
--- a/net/disk_cache/in_flight_backend_io.cc
+++ b/net/disk_cache/blockfile/in_flight_backend_io.cc
@@ -2,16 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "net/disk_cache/in_flight_backend_io.h"
+#include "net/disk_cache/blockfile/in_flight_backend_io.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/compiler_specific.h"
 #include "base/logging.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/histogram_macros.h"
+#include "net/disk_cache/blockfile/backend_impl.h"
+#include "net/disk_cache/blockfile/entry_impl.h"
+#include "net/disk_cache/blockfile/histogram_macros.h"
 
 // Provide a BackendImpl object to macros from histogram_macros.h.
 #define CACHE_UMA_BACKEND_IMPL_OBJ backend_