Split some long declarations of two variables in one line into two
separate declarations. Made more things const, made some consts
constexpr. Skip a variable entirely when it's only used once (and not
giving us some other benefit). Moved some declarations closer to their
variables' first uses.
Replace some Capitalised variable names with lower-case ones.
Change-Id: I3b8dac46530ba1c2e6100cb007b5487253304526
Reviewed-by: Marc Mutz <marc.mutz@qt.io>
f8d31aa7de