perf ui/gtk: Fix callchain display
perf ui/gtk: Fix callchain display

With current output field change, GTK browser cannot display callchain
information correctly since it couldn't determine where the symbol
column is.  This is a problem - just for now I changed to use the last
column since it'll work for most cases.

Also it has a same problem of the percentage as stdio code.

Signed-off-by: Namhyung Kim <5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org>
Cc: Arun Sharma <c2cb8b536bb785a11a9303a3d5590407e9ac6d77@fb.com>
Cc: Frederic Weisbecker <e8a1bf9163cb25e93cfd6540f223b3872ea7ee55@gmail.com>
Link: http://lkml.kernel.org/r/1401335910-16832-25-git-send-email-5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org
Signed-off-by: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@kernel.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs