ART: Add workaround of 4.14 kernel bug to 137-cfi

4.14 kernel has a bug: missing final null byte in /proc/$pid/cmdline.
This causes 137-cfi to fail on Pixel 4. The test creates a command based
on /proc/self/cmdline. Because of the bug the created command is
invalid.

The CL adds a workaround of the bug by adding the final null byte if it
misses.

Bug: https://issuetracker.google.com/issues/150189787
Test: Pixel 2/3/4
Test: 137-cfi
Change-Id: If161b0b37df4a691a502e95eda7697c81334a7f1
1 file changed