[DevTools] Replace usages of document with custom functions.

Source/devtools/front_end/components/Section.js

Index: Source/devtools/front_end/components/Section.js
diff --git a/Source/devtools/front_end/components/Section.js b/Source/devtools/front_end/components/Section.js
index 787fd8b23b9fed561320da5059fe49e66d6cbef1..1ce317b0e9c2257ee1f9308799e808d2a8cd7677 100644
--- a/Source/devtools/front_end/components/Section.js
+++ b/Source/devtools/front_end/components/Section.js
@@ -34,17 +34,17 @@
  */
 WebInspector.Section = function(title, subtitle)
 {
-    this.element = document.createElement("div");
+    this.element = createElement("div");
     this.element.className = "section";
     this.element._section = this;
 
-    this.headerElement = document.createElement("div");
+    this.headerElement = createElement("div");
     this.headerElement.className = "header";
 
-    this.titleElement = document.createElement("div");
+    this.titleElement = createElement("div");
     this.titleElement.className = "title";
 
-    this.subtitleElement = document.createElement("div");
+    this.subtitleElement = createElement("div");
     this.subtitleElement.className = "subtitle";
 
     this.headerElement.appendChild(this.subtitleElement);