Unwind stack past system libraries on Linux.

Native heap profiler traces on Linux are sometimes incomplete because unwinder
hits a function from a system library (i.e. no frame pointers), finds bad stack
frame and stops.

This CL implements stack scanning, so instead of stopping unwinder scans stack
for a valid frame pointer and resumes unwinding.


Review-Url: https://codereview.chromium.org/2276813002
Cr-Commit-Position: refs/heads/master@{#417343}
1 file changed