Add Content-Type header to net::ReportSender reports

net/http/transport_security_state.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_HTTP_TRANSPORT_SECURITY_STATE_H_
 #define NET_HTTP_TRANSPORT_SECURITY_STATE_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 234 matching lines @@
     // The URI reports are sent to if a valid OCSP response is not stapled
     GURL report_uri;
 
     // True if subdomains are subject to this policy
     bool include_subdomains;
   };
 
   // An interface for asynchronously sending HPKP violation reports.
   class NET_EXPORT ReportSenderInterface {
    public:
-    // Sends the given serialized |report| to |report_uri|.
-    virtual void Send(const GURL& report_uri, const std::string& report) = 0;
+    // Sends the given serialized |report| to |report_uri| with Content-Type
+    // header as specified in |content_type|.

[eroman, 2016/09/26 21:14:07]

Can you add a note that content-type should be non-empty?
(to avoid any confusion on interpretation -- empty is not a means to omit the
content-type parameter).

[estark, 2016/09/26 23:26:10]

Done.

+    virtual void Send(const GURL& report_uri,
+                      const std::string& content_type,

[eroman, 2016/09/26 21:14:07]

What about base::StringPiece for these parameters?

I don't feel too strongly either way.
However since these are just being supplied to make a copy, StringPiece does
eliminate a redundant copy.

[estark, 2016/09/26 23:26:10]

Done.

+                      const std::string& report) = 0;
 
     // Sets a callback to be called when report sending fails.
     virtual void SetErrorCallback(
         const base::Callback<void(const GURL&, int)>& error_callback) = 0;
 
    protected:
     virtual ~ReportSenderInterface() {}
   };
 
   // An interface for building and asynchronously sending reports when a
@@ skipping 322 matching lines @@
   // rate-limiting.
   ExpiringCache<std::string, bool, base::TimeTicks, std::less<base::TimeTicks>>
       sent_reports_cache_;
 
   DISALLOW_COPY_AND_ASSIGN(TransportSecurityState);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_TRANSPORT_SECURITY_STATE_H_