Roll src/third_party/perfetto 9129fad98516..68ff3171f360 (2 commits)

https://android.googlesource.com/platform/external/perfetto.git/+log/9129fad98516..68ff3171f360

git log 9129fad98516..68ff3171f360 --date=short --no-merges --format='%ad %ae %s'
2019-11-14 tneda@google.com perfetto-ui: Adding different viewing options for heap profile flamegraph
2019-11-14 tneda@google.com perfetto-ui: Integrate merging callsites with expanding

Created with:
  gclient setdep -r src/third_party/perfetto@68ff3171f360

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/perfetto-chromium-autoroll
Please CC perfetto-bugs@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

TBR=perfetto-bugs@google.com

Bug: None
Change-Id: Ic7aba1fdc5f8a07b231f8bc7b3647e725cb64c19
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1916628Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#715280}

DEPS

@@ -1301,7 +1301,7 @@ deps = {
   },
 
   'src/third_party/perfetto':
-    Var('android_git') + '/platform/external/perfetto.git' + '@' + '9129fad985163ea6114812a319754db19f967c3c',
+    Var('android_git') + '/platform/external/perfetto.git' + '@' + '68ff3171f360e157469cc3bdc009bbb1a950125c',
 
   'src/third_party/perl': {
       'url': Var('chromium_git') + '/chromium/deps/perl.git' + '@' + '6f3e5028eb65d0b4c5fdd792106ac4c84eee1eb3',