Before this change, setWindowSize converts the size in device-
independent pixels once, invokes adjustWindowSizeBasedOnSizeLimitsInDP,
and then restore the values in device-dependent pixels. This might
introduce a slight error and then SetSize be unexpectedly invoked.
Such SetSize call with a slightly different size might not invoke
the FramebufferSize callback, and then this blocked forever when
maximizing the window.
This change fixes this by adjusting the size limits instead of the
window size so that the window size is not modified unexpectedly.
Closes#1577
b5d4c834b8