Improve merging of header modifications in webRequest.OnHeadersReceived

chrome/browser/extensions/extension_webrequest_api.h

Index: chrome/browser/extensions/extension_webrequest_api.h
diff --git a/chrome/browser/extensions/extension_webrequest_api.h b/chrome/browser/extensions/extension_webrequest_api.h
index 71b25701856e4334225ac0766192184aebce0c1c..2016eb9520e33459316f0862b6ed8e0220ebea66 100644
--- a/chrome/browser/extensions/extension_webrequest_api.h
+++ b/chrome/browser/extensions/extension_webrequest_api.h
@@ -14,6 +14,7 @@
 #include "base/memory/singleton.h"
 #include "base/time.h"
 #include "chrome/browser/extensions/extension_function.h"
+#include "chrome/browser/extensions/extension_webrequest_api_helpers.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/extensions/url_pattern_set.h"
 #include "ipc/ipc_message.h"
@@ -33,10 +34,6 @@ class ListValue;
 class StringValue;
 }
 
-namespace extension_webrequest_api_helpers {
-struct EventResponseDelta;
-}
-
 namespace net {
 class AuthCredentials;
 class AuthChallengeInfo;
@@ -112,8 +109,9 @@ class ExtensionWebRequestEventRouter {
     bool cancel;
     GURL new_url;
     scoped_ptr<net::HttpRequestHeaders> request_headers;
-    // Contains all header lines after the status line, lines are \n separated.
-    std::string response_headers_string;
+    scoped_ptr<extension_webrequest_api_helpers::ResponseHeaders>
+        response_headers;
+
     scoped_ptr<net::AuthCredentials> auth_credentials;
 
     EventResponse(const std::string& extension_id,