Reorganize net/disk_cache into backend specific directories.

net/disk_cache/disk_cache_test_base.cc

Index: net/disk_cache/disk_cache_test_base.cc
diff --git a/net/disk_cache/disk_cache_test_base.cc b/net/disk_cache/disk_cache_test_base.cc
index 3cf98a86b140c09dd59c29e904f05f0c926aaea8..147d1846e8e0361e40170d2145835e90dc2c0786 100644
--- a/net/disk_cache/disk_cache_test_base.cc
+++ b/net/disk_cache/disk_cache_test_base.cc
@@ -11,13 +11,13 @@
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "net/base/test_completion_callback.h"
-#include "net/disk_cache/backend_impl.h"
 #include "net/disk_cache/cache_util.h"
 #include "net/disk_cache/disk_cache.h"
 #include "net/disk_cache/disk_cache_test_util.h"
-#include "net/disk_cache/mem_backend_impl.h"
+#include "net/disk_cache/memory/mem_backend_impl.h"
 #include "net/disk_cache/simple/simple_backend_impl.h"
 #include "net/disk_cache/simple/simple_index.h"
+#include "net/disk_cache/v2/backend_impl.h"
 
 DiskCacheTest::DiskCacheTest() {
   CHECK(temp_dir_.CreateUniqueTempDir());