That's surprising -- the Mac AMD trybots are the same exact machine model as your laptop.

Out of curiosity, if you force the screensaver to activate while the test is running, do you get different results? We are seeing the screensaver interfere with the screenshot_sync tests in another bug.

Yes, but I am on ElCapitan and the bots are on Yosemite. So it might be a bug Apple already fixed. I'll try with screensaver later.

Verified on both Mac Retina AMD and Intel 6000 with 10.11, and this test passes on both machines.  I think it's safe to say it's been fixed in the latest driver.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/42a2982f591aa146df148e3a6951411c1f801147

commit 42a2982f591aa146df148e3a6951411c1f801147
Author: qiankun.miao <qiankun.miao@intel.com>
Date: Mon Sep 26 19:28:05 2016

Remove shaderloop_do_while from expected fail list

BUG= 617820 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel;master.tryserver.chromium.android:android_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2367283002
Cr-Commit-Position: refs/heads/master@{#420960}

[modify] https://crrev.com/42a2982f591aa146df148e3a6951411c1f801147/content/test/gpu/gpu_tests/webgl2_conformance_expectations.py