tree dd8083a0c5ce5502f6e7dfb0ef041f23b6d15ca4
parent 61fb5fe766150b2a2cc25e266371525b2ff8266a
author Andreas Gampe <agampe@google.com> 1516067351 -0800
committer Andreas Gampe <agampe@google.com> 1516067351 -0800

Perfprofd: Fix missing symbol crash in stack script

It is possible we will not find a symbol for a frame in the backtrace.
Do not crash, print '???' instead.

Test: mmma system/extras/perfprofd
Test: manual
Change-Id: Ic91907c2f38adcbbd5979b7d1533df642ce763b3