Remove unused function

Found by ICC
qmljsreformatter.cpp(410): warning #177: function "<unnamed>::Rewriter::firstOnLine" was declared but never referenced

Change-Id: I7de033f80b0e4431b7f1ffff13fa77233116f0cb
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Reviewed-by: Marco Benelli <marco.benelli@theqtcompany.com>
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/libs/qmljs/qmljsreformatter.cpp

@@ -407,15 +407,6 @@ protected:
         return false;
     }
 
-    bool firstOnLine()
-    {
-        foreach (const QChar &c, _line) {
-            if (!c.isSpace())
-                return false;
-        }
-        return true;
-    }
-
     void addPossibleSplit(qreal badness, int offset = 0)
     {
         Split s;