Race conditions can cause `.uploader-window` to be visible with opacity of `0`. It will cause the user to have to refresh the page or inspect the element to hide it. Add a delay in `wp.media.view.UploaderWindow.hide()` to ensure that the uploader window is indeed hidden.

Props kovshenin.
Fixes #27341.


git-svn-id: https://develop.svn.wordpress.org/trunk@28838 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/js/media-views.js

@@ -3492,6 +3492,13 @@
 					$el.hide();
 				}
 			});
+
+			// https://core.trac.wordpress.org/ticket/27341
+			_.delay( function() {
+				if ( '0' === $el.css('opacity') && $el.is(':visible') ) {
+					$el.hide();
+				}
+			}, 500 );
 		}
 	});