Add an option to show file sizes in Runtime APEX test scripts' tree output.

Add option `--size` to `build/apex/art_apex_test.py`, showing the size
of each file in the tree output.

Add option `--print-sizes` to `build/apex/runtests.sh`, enabling the
previous option when running `build/apex/art_apex_test.py`. Rename the
short option of `--skip-build` from `-s` to `-B`, and reassign `-s` as
a short option for `--print-sizes`.

Test: art/build/apex/runtests.sh --print-tree --print-sizes
Change-Id: Ifff37b5e075f8972755d09709b7df1ce9a7a19f4
2 files changed