run-as: add ":fromRunAs" selector in seinfo.

It notifies libselinux that the setcontext request is from run-as.
And libselinux will set current process to runas_app domain, which
can execute app data files.

Bug: 118737210
Test: run CtsSimpleperfTestCases.
Change-Id: Ib94087f910786dd5d2a2b2e3b1bf76dfa7131ced
1 file changed