[GWP-ASan] Add inbuilt options parser.
Adds a modified options parser (shamefully pulled from Scudo, which
shamefully pulled it from sanitizer-common) to GWP-ASan. This allows
customers (Android) to parse options strings in a common way.
Depends on D94117.
AOSP side of these patches is staged at:
- sepolicy (sysprops should only be settable by the shell, in both root and
unrooted conditions):
https://android-review.googlesource.com/c/platform/system/sepolicy/+/1517238
- zygote updates:
https://android-review.googlesource.com/c/platform/frameworks/base/+/1515009
- bionic changes to add `gwp_asan.<process_name>` system property, and
GWP_ASAN_OPTIONS environment variable:
https://android-review.googlesource.com/c/platform/bionic/+/1514989
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D92696
15 files changed: