Don't clash signal names with other methods

In case when signal name clashes with other method name -
rename accordingly.
Remove some repeated signal declarations - they are already
declared in superclass.

Change-Id: Ie1430b85d6436d26996494fa44c7554fb354b6ce
Reviewed-by: hjk <hjk@qt.io>

src/plugins/qmljseditor/qmljseditor.h

@@ -80,7 +80,7 @@ signals:
     void selectedElementsChanged(QList<QmlJS::AST::UiObjectMember*> offsets,
                                  const QString &wordAtCursor);
 private:
-    void modificationChanged(bool);
+    void updateModificationChange(bool);
 
     void jumpToOutlineElement(int index);
     void updateContextPane();