QString multi-arg refactoring for increasing performance.

[dsm]

Hi, I search code base with .arg([^)]*).arg this reg exp and it founds more than 800 lines of code.

Using multi-arg methods gives more performance and less memory usage. Assign this issue to me.

[ra3xdh]

Yes, the QtCreator shows warning on arg().arg().arg() chains. It is widely used in the project. Such call is not recommended in new Qt versions. The refactoring would improve the code quality.