DevTools: Get rid of module initializers in the source tree

Source/devtools/front_end/documentation/module.json

 {
     "extensions": [
         {
             "type": "@WebInspector.ContextMenu.Provider",
             "contextTypes": [ "WebInspector.CodeMirrorTextEditor" ],
             "className": "WebInspector.DocumentationView.ContextMenuProvider"
         }
     ],
+    "dependencies": ["source_frame"],
     "scripts": [
         "WikiParser.js",
         "JSArticle.js",
         "CSSArticle.js",
         "DocumentationURLProvider.js",
         "DocumentationView.js"
     ]
 }