DevTools: move DOMExtension.js into ui module.

third_party/WebKit/Source/devtools/front_end/ui/DOMExtension.js

Index: third_party/WebKit/Source/devtools/front_end/ui/DOMExtension.js
diff --git a/third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js b/third_party/WebKit/Source/devtools/front_end/ui/DOMExtension.js
similarity index 97%
rename from third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js
rename to third_party/WebKit/Source/devtools/front_end/ui/DOMExtension.js
index a2d99dfa65f731160484df196a6927ced45df318..e073412aaef621871c76c4c8ae4433e359a8cd6b 100644
--- a/third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js
+++ b/third_party/WebKit/Source/devtools/front_end/ui/DOMExtension.js
@@ -812,22 +812,3 @@ function isEnterKey(event) {
 function isEscKey(event) {
   return event.keyCode === 27;
 }
-
-/**
- * @param {function()} callback
- * @suppressGlobalPropertiesCheck
- */
-function runOnWindowLoad(callback) {
-  /**
-   * @suppressGlobalPropertiesCheck
-   */
-  function windowLoaded() {
-    window.removeEventListener('DOMContentLoaded', windowLoaded, false);
-    callback();
-  }
-
-  if (document.readyState === 'complete' || document.readyState === 'interactive')
-    callback();
-  else
-    window.addEventListener('DOMContentLoaded', windowLoaded, false);
-}