Add Content-Type header to net::ReportSender reports

net/url_request/report_sender.h

Index: net/url_request/report_sender.h
diff --git a/net/url_request/report_sender.h b/net/url_request/report_sender.h
index f74899fd4c337511c618f3d319b9664e10e11ed7..4b8cebad26731916a784c2528b138cebd19086ad 100644
--- a/net/url_request/report_sender.h
+++ b/net/url_request/report_sender.h
@@ -55,6 +55,7 @@ class NET_EXPORT ReportSender
 
   // TransportSecurityState::ReportSenderInterface implementation.
   void Send(const GURL& report_uri, const std::string& report) override;
+  void SetContentTypeHeader(const std::string& content_type) override;
   void SetErrorCallback(const ErrorCallback& error_callback) override;
 
   // net::URLRequest::Delegate implementation.
@@ -69,6 +70,10 @@ class NET_EXPORT ReportSender
   // Owns the contained requests.
   std::set<URLRequest*> inflight_requests_;
 
+  // The value of the Content-Type header that should be sent on
+  // outgoing reports.
+  std::string content_type_;
+
   // Called when a sent report results in an error.
   ErrorCallback error_callback_;