GTTF: Add missing virtual destructors.

net/http/http_pipelined_host.h

Index: net/http/http_pipelined_host.h
diff --git a/net/http/http_pipelined_host.h b/net/http/http_pipelined_host.h
index b7732e60a8b8bca37fc0135d5da7b341bbe9435c..bb5ce4d71b2bcbf49787e3632c69ec10f6c4bfdc 100644
--- a/net/http/http_pipelined_host.h
+++ b/net/http/http_pipelined_host.h
@@ -43,6 +43,8 @@ class NET_EXPORT_PRIVATE HttpPipelinedHost {
 
   class Delegate {
    public:
+    virtual ~Delegate() {}
+
     // Called when a pipelined host has no outstanding requests on any of its
     // pipelined connections.
     virtual void OnHostIdle(HttpPipelinedHost* host) = 0;