The local group is a sequence of libraries in default (breadth-first)
order. It allows RTLD_LOCALLY loaded library to correctly relocate
symbols within its group (see test-cases).
Local group lookup is performed after main executable and ld_preloads.
Bug: 2643900
Bug: 15432753
Bug: 18186310
(cherry picked from commit cfa97f172d)
Change-Id: I5fa8c673f929e4652c738912c7ae078d7ec286d2
