Roll src/third_party/depot_tools fdf027a728e9..780e6bf8d438 (4 commits)

https://chromium.googlesource.com/chromium/tools/depot_tools.git/+log/fdf027a728e9..780e6bf8d438

git log fdf027a728e9..780e6bf8d438 --date=short --first-parent --format='%ad %ae %s'
2020-02-28 ehmaldonado@google.com gclient: Allow setting GCLIENT_PY3 to 0 to run on Python 2.
2020-02-27 ehmaldonado@google.com git-cl: Run PostUpload hooks via CLI.
2020-02-27 ehmaldonado@google.com presubmit_support: Refactor and add tests for DoPostUploadExecuter.
2020-02-27 vapier@chromium.org my_activity: search gerrit review too

Created with:
  gclient setdep -r src/third_party/depot_tools@780e6bf8d438

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/depot-tools-chromium-autoroll
Please CC agable@chromium.org 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

Bug: chromium:1042324,chromium:984182
Tbr: agable@chromium.org
Change-Id: Ia9f24c988a5ae885c745a6851746dd48b04799c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2079626Reviewed-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@{#745329}

DEPS

@@ -879,7 +879,7 @@ deps = {
   },
 
   'src/third_party/depot_tools':
-    Var('chromium_git') + '/chromium/tools/depot_tools.git' + '@' + 'fdf027a728e975bfc7eb2f2cd2b93eb5b768b818',
+    Var('chromium_git') + '/chromium/tools/depot_tools.git' + '@' + '780e6bf8d43870389e6eba66611c7f25c8e0f6f3',
 
   'src/third_party/devtools-frontend/src':
     Var('chromium_git') + '/devtools/devtools-frontend' + '@' + Var('devtools_frontend_revision'),