[DevTools] Prepare to move Popover to shadow DOM.

third_party/WebKit/Source/devtools/front_end/timeline/TimelineUIUtils.js

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  * Copyright (C) 2012 Intel 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 1385 matching lines @@
 
     /**
      * @param {?string} imageURL
      */
     function onGotImage(imageURL) {
       if (!imageURL) {
         callback();
         return;
       }
       var container = createElement('div');
+      UI.appendStyle(container, 'components/imagePreview.css');
       container.classList.add('image-preview-container', 'vbox', 'link');
       var img = container.createChild('img');
       img.src = imageURL;
       var paintProfilerButton = container.createChild('a');
       paintProfilerButton.textContent = Common.UIString('Paint Profiler');
       container.addEventListener('click', showPaintProfiler, false);
       callback(container);
     }
 
     function showPaintProfiler() {
@@ skipping 879 matching lines @@
    * @param {string=} warningType
    */
   appendWarningRow(event, warningType) {
     var warning = Timeline.TimelineUIUtils.eventWarning(event, warningType);
     if (warning)
       this.appendElementRow(Common.UIString('Warning'), warning, true);
   }
 };
 
 Timeline.TimelineUIUtils._categoryBreakdownCacheSymbol = Symbol('categoryBreakdownCache');