Remove WAPI-related code, except the type definition of ResourceEntry.

google_apis/drive/drive_common_callbacks.h

Index: google_apis/drive/drive_common_callbacks.h
diff --git a/google_apis/drive/drive_common_callbacks.h b/google_apis/drive/drive_common_callbacks.h
index 234c531f2b5f4d15ce59e1056b28a85ba613d9a7..e1cb6b624d1c857233f902c11c915d734ca55b3c 100644
--- a/google_apis/drive/drive_common_callbacks.h
+++ b/google_apis/drive/drive_common_callbacks.h
@@ -15,12 +15,6 @@ namespace google_apis {
 class AboutResource;
 class AppList;
 class ResourceEntry;
-class ResourceList;
-
-// Callback used for getting ResourceList.
-typedef base::Callback<void(GDataErrorCode error,
-                            scoped_ptr<ResourceList> resource_list)>
-    GetResourceListCallback;
 
 // Callback used for getting ResourceEntry.
 typedef base::Callback<void(GDataErrorCode error,