If a EM_SETPARAFORMAT message is sent to the richedit control with bits
in the dwMask field that correspond to PARAFORMAT2 fields, then these
fields should be ignored.  Instead data was copied from outside of the
structure.

Using the WS_VSCROLL style causes the ES_AUTOVSCROLL option to be set,
and using the WS_HSCROLL style causes the ES_AUTOHSCROLL flag to be
set (except with richedit v1.0).

user32/tests: Add support for testing only some bits of wparam or lparam. Make some more messages optional.

comdlg32: If a measurement system isn't specified use the default one and update the Flags field to reflect this.

This gives a minor performance improvement.

Based on a patch by Mike Ruprecht.