[Bug 55771] New: uxtheme:system - test_ShouldSystemUseDarkMode() fails on Windows 7 to 10 1909

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=55771

Bug ID: 55771
           Summary: uxtheme:system - test_ShouldSystemUseDarkMode() fails
                    on Windows 7 to 10 1909
           Product: Wine
           Version: unspecified
          Hardware: x86-64
                OS: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: uxtheme
          Assignee: [e-mail]
          Reporter: [e-mail]

uxtheme:system - test_ShouldSystemUseDarkMode() fails on Windows 7 to 10 1909.
Mostly ShouldSystemUseDarkMode() returns various error codes.

Windows 7:
system.c:2628: Test failed: ShouldSystemUseDarkMode set last error: 5.

Windows 8:
system.c:2629: Test failed: Expected value 0, got -2147024890.

Windows 10 1507:
system.c:2623: this is the last test seen before the exception
03f8:system: unhandled exception c0000005 at 74A58B41

Windows 10 1607:
system.c:2628: Test failed: ShouldSystemUseDarkMode set last error: 0.
system.c:2629: Test failed: Expected value 0, got -2147467259.

Windows 10 1709:
system.c:2629: Test failed: Expected value 0, got -2147467261.

Windows 10 1809:
system.c:2629: Test failed: Expected value 0, got 1.

See: https://test.winehq.org/data/patterns.html#uxtheme:system

Where: 5 == ERROR_ACCESS_DENIED
       -2147467261 == 0x80004003 == E_POINTER
       -2147467259 == 0x80004005 == E_FAIL
       -2147024890 == 0x80070006 == ERROR_INVALID_HANDLE

Are we sure that the entry point 138 really points to ShouldSystemUseDarkMode()
on early Windows versions? Because it looks more like it points to random APIs
that may expect more parameters and end up failing in varying ways.