Support retrieval of raw headers from network stack

net/http/http_net_log_params.h

Index: net/http/http_net_log_params.h
diff --git a/net/http/http_net_log_params.h b/net/http/http_net_log_params.h
index 5a5e84b917b328c1973601a43555e3645e84532d..4331a0f2c1d659e645ad63ba6bb9064ef0f01ed2 100644
--- a/net/http/http_net_log_params.h
+++ b/net/http/http_net_log_params.h
@@ -41,6 +41,10 @@ class NetLogHttpRequestParameter : public NetLog::EventParameters {
     return dict;
   }
 
+  const HttpRequestHeaders& GetHeaders() const {
+    return headers_;
+  }
+
  private:
   ~NetLogHttpRequestParameter() {}
 
@@ -72,6 +76,10 @@ class NetLogHttpResponseParameter : public NetLog::EventParameters {
     return dict;
   }
 
+  const HttpResponseHeaders& GetHeaders() const {
+    return *headers_;
+  }
+
  private:
   ~NetLogHttpResponseParameter() {}