Fixes #3545. Superview most focused view not sync with the overlapped view.

[BDisp]

Fixes

• Fixes When adding more than one Window + TextView together with a MenuBar, the displayed text changes to the text of the first added Window #3545

Proposed Changes/Todos

• Calling BringOverlappedTopToFront method on the Application.Begin.

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[luizfernandonb]

@BDisp Will this only be fixed in v2? Not in v1?

[BDisp]

@BDisp Will this only be fixed in v2? Not in v1?

I will submit a PR for v1 soon.

[BDisp]

Done for v1 on the PR #3550.