comdlg32/tests: Vista can return a failure from StartDoc when using the XPS driver - don't fail the test in this case.

Should make it a bit clearer what's happening in some cases.

glWeightPointerARB() obviously accepts floating point data.

The code tried to optimize the usage of the 32bit A(scii) winmm API
with a 16bit driver.

gdi32: Move 16-bit functions not exported in gdi32.dll into files compiled only when 16-bit functionality is enabled.

wineoss.drv: Use CP_UNIXCP instead of CP_ACP for converting strings that come from system library functions or system headers.

widl: Fix typos in write_remoting_arg which caused ref pointers to unions to not result in direct calls to NonEncapsulatedUnion/EncapsulatedUnion functions.

With thanks to Dmitry for spotting this.

user32/tests: Ignore SPI_ICONVERTICALSPACING notifications. Don't reset mouse buttons if setting failed.