extensions: Cleanup class/struct fwd declarations

extensions/browser/api/declarative_webrequest/webrequest_action.h

Index: extensions/browser/api/declarative_webrequest/webrequest_action.h
diff --git a/extensions/browser/api/declarative_webrequest/webrequest_action.h b/extensions/browser/api/declarative_webrequest/webrequest_action.h
index 6109eb0f2e244903523c9231cd4d8d56d437a4e8..bd8fd070cccc08ff7c36e8627aca069514489a53 100644
--- a/extensions/browser/api/declarative_webrequest/webrequest_action.h
+++ b/extensions/browser/api/declarative_webrequest/webrequest_action.h
@@ -19,10 +19,7 @@
 #include "extensions/common/api/events.h"
 #include "url/gurl.h"
 
-class WebRequestPermission;
-
 namespace base {
-class DictionaryValue;
 class Time;
 class Value;
 }
@@ -37,10 +34,6 @@ class InfoMap;
 struct WebRequestData;
 }
 
-namespace net {
-class URLRequest;
-}
-
 namespace re2 {
 class RE2;
 }