Move ExtensionWarningService and ExtensionsWarningSet to extensions.

chrome/browser/extensions/api/downloads/downloads_api.h

Index: chrome/browser/extensions/api/downloads/downloads_api.h
diff --git a/chrome/browser/extensions/api/downloads/downloads_api.h b/chrome/browser/extensions/api/downloads/downloads_api.h
index 916582ed75f33f321880d5718eb6c5b41fe9d6c9..aaf92d327043a9ee9c23af3ad772c9f2dc4ccfc5 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api.h
+++ b/chrome/browser/extensions/api/downloads/downloads_api.h
@@ -14,11 +14,11 @@
 #include "chrome/browser/download/download_danger_prompt.h"
 #include "chrome/browser/download/download_path_reservation_tracker.h"
 #include "chrome/browser/extensions/chrome_extension_function.h"
-#include "chrome/browser/extensions/extension_warning_set.h"
 #include "chrome/common/extensions/api/downloads.h"
 #include "content/public/browser/download_manager.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extension_registry_observer.h"
+#include "extensions/browser/warning_set.h"
 
 class DownloadFileIconExtractor;
 class DownloadQuery;
@@ -324,7 +324,7 @@ class ExtensionDownloadsEventRouter
       base::FilePath* determined_filename,
       extensions::api::downloads::FilenameConflictAction*
         determined_conflict_action,
-      extensions::ExtensionWarningSet* warnings);
+      extensions::WarningSet* warnings);
 
   // A downloads.onDeterminingFilename listener has returned. If the extension
   // wishes to override the download's filename, then |filename| will be