KQuickStyleItem: Simplify the updatePolish

Aleix Pol Gonzalez requested to merge work/small-optimisation into master
  • Don't cast the devicePixelRatio into a float unnecessarily, use the same type we get.
  • Only keep the texture for visible items.
  • Do not re-create the texture if the sizes haven't changed.
Edited by Aleix Pol Gonzalez

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