Use gcc-4.8 when compiling for Ubuntu14. Rename the CT tasks to make it
clear their child tasks run on Ubuntu14.
Move to Debian-9.1 bots created with the changes in
https://skia-review.googlesource.com/c/31281 and
https://skia-review.googlesource.com/c/31820
Change the cache dir used by the ct_skps recipe so that changing the
bot name doesn't invalidate the cache.
Bug: skia:6921
Bug: skia:6818
No-Try: true
Change-Id: Idaac8187427b5c2c7bffe66ad6674496b8cd0c0e
Reviewed-on: https://skia-review.googlesource.com/31242
Commit-Queue: Ravi Mistry <rmistry@google.com>
Reviewed-by: Ben Wagner <benjaminwagner@google.com>
Reviewed-by: Ravi Mistry <rmistry@google.com>
