DevTools: move DOMExtension.js into ui module.

third_party/WebKit/Source/devtools/front_end/platform/utilities.js

Index: third_party/WebKit/Source/devtools/front_end/platform/utilities.js
diff --git a/third_party/WebKit/Source/devtools/front_end/platform/utilities.js b/third_party/WebKit/Source/devtools/front_end/platform/utilities.js
index 1edf9b970a48ff10343a6efb4712211a02eae093..73f1da98a56343803e2963659a181f2b22732206 100644
--- a/third_party/WebKit/Source/devtools/front_end/platform/utilities.js
+++ b/third_party/WebKit/Source/devtools/front_end/platform/utilities.js
@@ -1440,3 +1440,23 @@ Map.prototype.diff = function(other, isEqual) {
   }
   return {added: added, removed: removed, equal: equal};
 };
+
+/**
+ * TODO: move into its own module
+ * @param {function()} callback
+ * @suppressGlobalPropertiesCheck
+ */
+function runOnWindowLoad(callback) {
+  /**
+   * @suppressGlobalPropertiesCheck
+   */
+  function windowLoaded() {
+    self.removeEventListener('DOMContentLoaded', windowLoaded, false);
+    callback();
+  }
+
+  if (document.readyState === 'complete' || document.readyState === 'interactive')
+    callback();
+  else
+    self.addEventListener('DOMContentLoaded', windowLoaded, false);
+}