Make QmlJS scope building more flexible.

Instead of only maintaining a flat list of scopes, actually store the
global, component chain, root object, scope object, function, id and js
scopes separately.

src/plugins/qmljseditor/qmljscodecompletion.cpp

@@ -189,7 +189,7 @@ public:
         _properties.clear();
         _currentObject = 0;
 
-        foreach (const Interpreter::ObjectValue *scope, _context->scopeChain())
+        foreach (const Interpreter::ObjectValue *scope, _context->scopeChain().all)
             enumerateProperties(scope);
 
         return _properties;