Canvas related kill switches

[atuchin-m]

For https://github.com/brave/brave-variations/issues/1060 PR to production: https://github.com/brave/brave-variations/pull/1068

Both features need to be disabled.

We use max_version: 125.* because cr126 got the fix in the code, so we don't need to cover it. min_version isn't set because Finch config disables:

1. EvictionUnlocksResources for >= cr124 (for <= cr123 it's disabled in the code )
2. Canvas2DHibernation for all the revisions.

P.S. Chrome has 2 separate studies, but it looks less reliable.

Steps to reproduce: https://issues.chromium.org/u/0/issues/341105739

[kjozwiak]

Win 11 x64 verifications

Nightly - CanvasKillSwitches:Disabled_EmergencyKillSwitch

Verification PASSED on Win 11 x64 using the following build(s):

Brave | 1.68.25 Chromium: 125.0.6422.60 (Official Build) nightly (64-bit)
-- | --
Revision | aa179dbee72ac0ca0412be64803ecbe931bb3a9e
OS | Windows 11 Version 23H2 (Build 22631.3593)

• launched 1.68.25 Chromium: 125.0.6422.60 using brave.exe --enable-logging=stderr --reset-variation-state --variations-server-url=https://variations.bravesoftware.com/seed
• ensured that CanvasKillSwitches:Disabled_EmergencyKillSwitch wasn't being displayed under brave://version
• opened ~5 tabs and then visited https://www.w3schools.com/html/tryit.asp?filename=tryhtml5_canvas_tut_path2
  • notice that the canvas is completely blank (should be displaying a circle)
• Restarted using brave.exe --enable-logging=stderr --reset-variation-state --variations-server-url=https://variations.bravesoftware.com/seed
• ensured that CanvasKillSwitches:Disabled_EmergencyKillSwitch was being displayed under brave://version
• ensured that the canvas is being displayed/visible

Broken	Fixed

Release - CanvasKillSwitches:Disabled_EmergencyKillSwitch

Brave | 1.66.110 Chromium: 125.0.6422.60 (Official Build) (64-bit)
-- | --
Revision | de593d76e2ca4d02faa85bf1ca27bcf3ee46793c
OS | Windows 11 Version 23H2 (Build 22631.3593)

• launched 1.66.110 Chromium: 125.0.6422.60 using brave.exe --enable-logging=stderr --reset-variation-state --variations-server-url=https://variations.bravesoftware.com/seed
• ensured that CanvasKillSwitches:Disabled_EmergencyKillSwitch wasn't being displayed under brave://version
• opened ~5 tabs and then visited https://www.w3schools.com/html/tryit.asp?filename=tryhtml5_canvas_tut_path2
  • notice that the canvas is completely blank (should be displaying a circle)
• Restarted using brave.exe --enable-logging=stderr --reset-variation-state --variations-server-url=https://variations.bravesoftware.com/seed
• ensured that CanvasKillSwitches:Disabled_EmergencyKillSwitch was being displayed under brave://version
• ensured that the canvas is being displayed/visible

Broken	Fixed

[kjozwiak]

Pixel 6 running Android 14 verifications

Release - CanvasKillSwitches:Disabled_EmergencyKillSwitch

Verification PASSED on Pixel 6 running Android 14 using the following build(s):

Brave | 1.66.110 Chromium: 125.0.6422.60 (Official Build) (64-bit)
--- | ---
Revision | de593d76e2ca4d02faa85bf1ca27bcf3ee46793c
OS | Android 14; Build/AP21.240305.005; 34; REL

• launched 1.66.110 Chromium: 125.0.6422.60 and ensured that Brave was pointing to https://variations.brave.com/seed
• ensured that CanvasKillSwitches:Disabled_EmergencyKillSwitch wasn't being displayed under brave://version
• opened ~5 tabs and then visited https://www.w3schools.com/html/tryit.asp?filename=tryhtml5_canvas_tut_path2
  • notice that the canvas is completely blank (should be displaying a circle)
• uninstalled/re-installed Brave but ensured that it's pointing to https://variations.bravesoftware.com/seed (staging)
• ensured that CanvasKillSwitches:Disabled_EmergencyKillSwitch was being displayed under brave://version
• ensured that the canvas is being displayed/visible (using the same STR/Cases mentioned above)

Broken	Fixed