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

net/spdy/write_blocked_list.h

Index: net/spdy/write_blocked_list.h
diff --git a/net/spdy/write_blocked_list.h b/net/spdy/write_blocked_list.h
index 76d22da257a577b3dd371aa7668e6a7094c96c56..cb5599760eb8bfc85c7573f919cf86b61bd0ae7a 100644
--- a/net/spdy/write_blocked_list.h
+++ b/net/spdy/write_blocked_list.h
@@ -9,8 +9,8 @@
 
 #include <algorithm>
 #include <deque>
+#include <unordered_map>
 
-#include "base/containers/hash_tables.h"
 #include "base/logging.h"
 #include "net/spdy/spdy_protocol.h"
 
@@ -151,7 +151,7 @@ class WriteBlockedList {
  private:
   friend class net::test::WriteBlockedListPeer;
 
-  typedef base::hash_map<IdType, SpdyPriority> StreamToPriorityMap;
+  using StreamToPriorityMap = std::unordered_map<IdType, SpdyPriority>;
 
   void AddStream(IdType stream_id, SpdyPriority priority, bool push_back) {
     priority = ClampPriority(priority);