DevTools: [CSS] promisify CSS domain

Source/devtools/front_end/platform/utilities.js

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 1465 matching lines @@
  */
 Promise.prototype.spread = function(callback)
 {
     return this.then(spreadPromise);
 
     function spreadPromise(arg)
     {
         return callback.apply(null, arg);
     }
 }
+
+/**
+ * @param {T} defaultValue
+ * @return {!Promise.<T>}
+ * @template T
+ */
+Promise.prototype.catchException = function(defaultValue) {
+    return this.catch(function (error) {
+        console.error(error);
+        return defaultValue;
+    });
+}