Re-add the QUIC DCHECK to ensure packets are always sent in the order of

net/base/linked_hash_map.h

Index: net/base/linked_hash_map.h
diff --git a/net/base/linked_hash_map.h b/net/base/linked_hash_map.h
index 7948647df05913ae86de3eb3eaeacbb11fcf7967..b024ca1d5361d46f958051b096d668b61412ce6c 100644
--- a/net/base/linked_hash_map.h
+++ b/net/base/linked_hash_map.h
@@ -79,6 +79,28 @@ class linked_hash_map {
     return list_.rend();
   }
 
+  // Front and back accessors common to many stl containers.
+
+  // Returns the earliest-inserted element
+  const value_type& front() const {

[ramant (doing other things), 2014/08/15 01:51:33]

We are only using back(), added front() to be consistent. Hope that is ok.

+    return list_.front();
+  }
+
+  // Returns the earliest-inserted element.
+  value_type& front() {
+    return list_.front();
+  }
+
+  // Returns the most-recently-inserted element.
+  const value_type& back() const {
+    return list_.back();
+  }
+
+  // Returns the most-recently-inserted element.
+  value_type& back() {
+    return list_.back();
+  }
+
   // Clears the map of all values.
   void clear() {
     map_.clear();