Force sRGB color profile on Mac for pixel tests

content/test/gpu/gpu_tests/color_profile_manager.py

Index: content/test/gpu/gpu_tests/color_profile_manager.py
diff --git a/content/test/gpu/gpu_tests/color_profile_manager.py b/content/test/gpu/gpu_tests/color_profile_manager.py
new file mode 100644
index 0000000000000000000000000000000000000000..e90becdc81ae4fbb0ee4f0792acd5d64f6f4ead6
--- /dev/null
+++ b/content/test/gpu/gpu_tests/color_profile_manager.py
@@ -0,0 +1,26 @@
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import sys
+
+if sys.platform.startswith('darwin'):
+  from gpu_tests import color_profile_manager_mac
+
+class ColorProfileManager(object):
+  _display_profile_url_map = {}

[Ken Russell (switch to Gerrit), 2017/06/20 22:55:02]

This is a class-scoped variable as written. To make it instance-scoped, set it
up in __init__ like:
  self._display_profile_url_map = {}
before the Mac-specific code.

[ccameron, 2017/06/21 06:45:42]

Thanks. Ended up deleting this from the atexit part.

+
+  def __init__(self):
+    if sys.platform.startswith('darwin'):
+      self._display_profile_url_map = \
+        color_profile_manager_mac.GetDisplaysToProfileURLMap()
+
+  def ForceSRGB(self):

[Ken Russell (switch to Gerrit), 2017/06/20 22:55:02]

Do you think it's worth registering an atexit handler which will call Restore on
itself if it hasn't already been called? Thinking of something like this:

https://pastebin.com/mGK5HMZb

The various frameworks (typ, I think, is responsible for this now) do call
TearDownProcess even if Ctrl-C is pressed, so perhaps this added complexity
isn't needed.

Please add documentation saying that if ForceSRGB is called, Restore must be
called.

We should give the Swarming team a heads-up that we are going to be changing
system-wide settings which may affect subsequent test runs.

[ccameron, 2017/06/21 06:45:42]

Good idea -- I updated this to register an atexit handler, and just have a
method ForceUntilExitSRGB, which has these calls wrapped into one.

+    for display_id in self._display_profile_url_map:
+      color_profile_manager_mac.SetDisplayCustomProfile(
+          display_id, color_profile_manager_mac.GetSRGBProfileURL())
+
+  def Restore(self):
+    for display_id in self._display_profile_url_map:
+      color_profile_manager_mac.SetDisplayCustomProfile(
+          display_id, self._display_profile_url_map[display_id])