DevTools: Only provide static script content to UISourceCode

third_party/WebKit/Source/devtools/front_end/common/StaticContentProvider.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 /**
  * @implements {Common.ContentProvider}
  * @unrestricted
  */
 Common.StaticContentProvider = class {
   /**
    * @param {string} contentURL
    * @param {!Common.ResourceType} contentType
-   * @param {function():!Promise<string>} lazyContent
+   * @param {function():!Promise<?string>} lazyContent
    */
   constructor(contentURL, contentType, lazyContent) {
     this._contentURL = contentURL;
     this._contentType = contentType;
     this._lazyContent = lazyContent;
   }
 
   /**
    * @param {string} contentURL
    * @param {!Common.ResourceType} contentType
@@ skipping 19 matching lines @@
    */
   contentType() {
     return this._contentType;
   }
 
   /**
    * @override
    * @return {!Promise<?string>}
    */
   requestContent() {
-    return /** @type {!Promise<?string>} */ (this._lazyContent());
+    return this._lazyContent();
   }
 
   /**
    * @override
    * @param {string} query
    * @param {boolean} caseSensitive
    * @param {boolean} isRegex
    * @param {function(!Array.<!Common.ContentProvider.SearchMatch>)} callback
    */
   searchInContent(query, caseSensitive, isRegex, callback) {
     /**
-     * @param {string} content
+     * @param {?string} content
      */
     function performSearch(content) {
-      callback(Common.ContentProvider.performSearchInContent(content, query, caseSensitive, isRegex));
+      callback(Common.ContentProvider.performSearchInContent(content || '', query, caseSensitive, isRegex));
     }
 
     this._lazyContent().then(performSearch);
   }
 };