Issue #1603 - Part 1: Reorganize ScriptLoader/ScriptElement

- Moves scripting parts of DOM into 'dom/script'
- Renames nsScript{Loader/Element} to Script{Loader/Element}
- Adjusts all callers

dom/html/HTMLScriptElement.cpp

@@ -37,7 +37,7 @@ HTMLScriptElement::WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto)
 HTMLScriptElement::HTMLScriptElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo,
                                      FromParser aFromParser)
   : nsGenericHTMLElement(aNodeInfo)
-  , nsScriptElement(aFromParser)
+  , ScriptElement(aFromParser)
 {
   AddMutationObserver(this);
 }