Fix counters for regions following `else if`s, fix
the counters for `else if` conditions, and fix
handling of `break` statements. Also while here,
clean up the handling of branch exit regions such
that we don't generate multiple overlapping
regions for each branch, but a single region at
the end of the entire `if` statement that accounts
for all exiting control flow.
rdar://104078910
rdar://104079242
Previously we were walking into the
PropertyWrapperValuePlaceholderExpr when generating
coverage for a property wrapper backing initializer.
This meant that we were duplicating the coverage of
the initializer expression, and it could cause
crashes if a refined counter was introduced within
the top-most expression region, such as with a
throwing expression in a `try!`.
rdar://118939162
This replaces some of the existing checks, and
ensures that we don't emit coverage maps for
property wrapper backing initializers that don't
contain user code.
rdar://99931619
Previously we were creating a SILProfiler for
such functions, but weren't actually emitting the
increment, leading to missed coverage.
Part of the fix for rdar://99931619
