Reland 'Convert //net and //chromecast to std::unordered_*'

net/disk_cache/blockfile/backend_impl_v3.h

Index: net/disk_cache/blockfile/backend_impl_v3.h
diff --git a/net/disk_cache/blockfile/backend_impl_v3.h b/net/disk_cache/blockfile/backend_impl_v3.h
index 727c3a6be08e52827c1092b70f013f9e41fc1556..04c7ccef16c99b0f006a810fd78b963d1af087ab 100644
--- a/net/disk_cache/blockfile/backend_impl_v3.h
+++ b/net/disk_cache/blockfile/backend_impl_v3.h
@@ -9,7 +9,8 @@
 
 #include <stdint.h>
 
-#include "base/containers/hash_tables.h"
+#include <unordered_map>
+
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ -198,7 +199,7 @@ class NET_EXPORT_PRIVATE BackendImplV3 : public Backend {
 
  private:
   friend class EvictionV3;
-  typedef base::hash_map<CacheAddr, EntryImplV3*> EntriesMap;
+  using EntriesMap = std::unordered_map<CacheAddr, EntryImplV3*>;
   class IteratorImpl;
   class NotImplementedIterator;
   class Worker;