runtime: fix callee tracking in traceback printing
In CL 466099, we accidentally stopped tracking callees while unwinding
inlined frames during traceback printing. The effect is that if you
have a call stack like:
f -> wrapper -> inlined into wrapper -> panic
when considering whether to print the frame for "wrapper", we'll think
that wrapper called panic, rather than the inlined function.
Fix this in the traceback code and add a test.
Change-Id: I30ec836cc316846ce93de94e28a650e23dca184e
Reviewed-on: https://go-review.googlesource.com/c/go/+/476579
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>