fix_args: add QString to the replacement patterns

Plain `QString`s are no more importable because converted to Python
Unicode strings.

Use English in the example

example-args.py

@@ -1,7 +1,9 @@
-from PyQt4.Qt import (QLabel, qApp)
+from PyQt4.Qt import (QLabel, QString, qApp)
 
 class Window(QLabel):
     def foo(self, value, tr=None):
-        self.tr("Messaggio %1").arg(self.getText())  # cose
-        tr("Messaggio %1 e %2").arg(self.getText()).arg(value)
-        qApp.translate("Messaggio %1 e %2").arg(self.getText(), value)
+        self.tr("Message %1").arg(self.getText())  # some comment
+        tr("Message %1 and %2").arg(self.getText()).arg(value)
+        qApp.translate("Message %1 and %2").arg(self.getText(), value)
+        QString("Message %1 and %2").arg(self.getText(), value)
+        print(tr("Some message %1").arg(value))

my_fixes/fix_args.py

@@ -23,7 +23,7 @@ class FixArgs(fixer_base.BaseFix):
     PATTERN = """
     power<
       before=any*
-      tr=('tr' | 'translate') trailer< '(' message=any ')' >
+      tr=('tr' | 'translate' | 'QString') trailer< '(' message=any ')' >
       {args}
       rest=any*
     >