As part of fixing some bugs like CORE-13149, extend the tests to include more detailed examination of rendering functions. Extend the RedrawWindow test to include tests of all flags. As part of it, I am also testing the 2-point states of the render areas.
I moved the original test without changes into a separate function GetMessageRedrawWindowTest. For the flag tests I added FlagsRedrawWindowTest function. It sequentially tests the RedrawWindow with different flag combinations and compares the results with those discovered in Windows XP and Windows 11 (the values in both versions confirmed to be identical).
The API test turned out well in ReactOS, the only deviation was that in many cases (whenever the RDW_INVALIDATE flag is present) a WM_ERASEBKGND message is received after the window is rendered without the RDW_ERASE flag.
(this is what I'm focusing on now in https://github.com/turican0/reactos/tree/fix-RDW_ERASE-in-co_UserRedrawWindow, but before I merge it, I want to create more API tests)
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