Regarding "flags are processed too late" - that's true, but does that matter much? On Android heap profiler misses ~2 MiB, but only ~300 KiB with when startup tracing is used. And all that memory is "constant", i.e. doesn't depend on the payload.

BTW, heap profiling can also be enabled via chrome://flags.

Also, we have some instructions here: https://chromium.googlesource.com/chromium/src/+/master/docs/memory-infra/heap_profiler.md

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/52959d9d66294837b7fe94f4b7a501157c04b6e0

commit 52959d9d66294837b7fe94f4b7a501157c04b6e0
Author: catapult-deps-roller@chromium.org <catapult-deps-roller@chromium.org>
Date: Tue Jun 06 22:27:25 2017

Roll src/third_party/catapult/ 264d6b2eb..dc460e541 (1 commit)

https://chromium.googlesource.com/external/github.com/catapult-project/catapult.git/+log/264d6b2ebb8b..dc460e541ad9

$ git log 264d6b2eb..dc460e541 --date=short --no-merges --format='%ad %ae %s'
2017-06-06 erikchen Add support for symbolization of native heap dumps on official builds.

Created with:
  roll-dep src/third_party/catapult
BUG=729151


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

If the roll is causing failures, see:
http://www.chromium.org/developers/tree-sheriffs/sheriff-details-chromium#TOC-Failures-due-to-DEPS-rolls


CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_optional_gpu_tests_rel
TBR=sullivan@chromium.org

Change-Id: Iac69f99dda67b2ec6bf2c14e3ec39aff6dbad74e
Reviewed-on: https://chromium-review.googlesource.com/526259
Reviewed-by: <catapult-deps-roller@chromium.org>
Commit-Queue: <catapult-deps-roller@chromium.org>
Cr-Commit-Position: refs/heads/master@{#477438}
[modify] https://crrev.com/52959d9d66294837b7fe94f4b7a501157c04b6e0/DEPS