Fix braino in Jit::PostZygoteFork.

The logic for mapping boot image methods after fork is for a child
zygote, so we should check as such (just as the comment mentions).

Not doing the check leads to a race for a forked process with a child
zygote, which if the boot image methods are not yet mapped, it would try
to map them twice.

Test: boots and no crashes in webview forked processes.
Bug: 119800099
Change-Id: I19767d8e3b992e51274e232b41e10a0fe363f284
1 file changed