enable BraveWebcompatExceptionsService in Nightly

[arthuredelstein]

Resolves #1179

[github-actions]

✅ Test Seed Generated Successfully

To apply the test seed:

1. Desktop: Launch the browser with --variations-pr=1180.
   Android: Set the command line to --variations-pr=1180 in debug menu, restart the browser.
   iOS: Set Variations PR to 1180 in Brave Core Switches debug menu, restart the browser.
2. Wait 5-10 seconds to fetch the seed.
3. Restart the browser to apply the seed.
4. Ensure Active Variations section at brave://version starts with the expected seed version (see below).

Seed Details

Parameter	Value
Version	pull/1180@58b8428788ce101b28afc318eea84c967bdf411f
Uploaded	Tue, 13 Aug 2024 19:30:36 GMT
PR commit	9ba9268
Base commit	fcf9b8a
Merge commit	58b8428
Serial number	1c6298f5265442a70586784ea5f62230

[kjozwiak]

Windows verification(s):

Nightly - BraveWebcompatExceptionsServiceStudy:Enabled

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

Brave | 1.71.2 Chromium: 128.0.6613.27 (Official Build) nightly (64-bit)
-- | --
Revision | f295da0b492fb883d420f5046589ca81a40c3d30
OS | Windows 11 Version 23H2 (Build 22631.4037)

• launched/re-launched 1.71.2 Chromium: 128.0.6613.27 using brave.exe --enable-logging=stderr --variations-pr=1180
• ensured that pull/1180@58b8428788ce101b28afc318eea84c967bdf411f via brave://version under Active variations
• ensured that BraveWebcompatExceptionsServiceStudy:Enabled via brave://version
• visited https://browserleaks.com/javascript and clicked on the shields panel
• ensured that the number of fingerprintable APIs appears next to Block fingerprinting via the shields panel
• ensured that clicking on the number opens a Fingerprinting protections applied panel with a list of FP API's
• ensured that you toggle various fingerprintable APIs without any issues

Example	Example	Example	Example	Example

Nightly - min_version condition not met

Brave | 1.70.65 Chromium: 128.0.6613.27 (Official Build) nightly (64-bit)
-- | --
Revision | 8bf2d6fd36dc289a5918c6c06969c161d81717dc
OS | Windows 11 Version 23H2 (Build 22631.4037)

• launched/re-launched 1.70.65 Chromium: 128.0.6613.27 using brave.exe --enable-logging=stderr --variations-pr=1180
• ensured that pull/1180@58b8428788ce101b28afc318eea84c967bdf411f via brave://version under Active variations
• ensured that BraveWebcompatExceptionsServiceStudy:Enabled was not being displayed via brave://version
• visited https://browserleaks.com/javascript and clicked on the shields panel
• ensured there's no Advanced controls/switches re: being able to disable fingerprintable API's.

Example	Example

[kjozwiak]

Android verification(s):

Quick Note: used the STR/Cases outlined via brave/brave-browser#37074 (comment) to quickly check/ensure that BraveWebcompatExceptionsServiceStudy was being applied.

Nightly - BraveWebcompatExceptionsServiceStudy:Enabled

Verification PASSED on Pixel 6 running Android 15 using the following build(s):

Brave | 1.71.5 Chromium: 128.0.6613.40 (Official Build) canary (64-bit)
--- | ---
Revision | efb921587bc19aa9e63dd43cd4d71c62db311539
OS | Android 15; Build/AP31.240617.010; 35; REL

• launched 1.71.5 Chromium: 128.0.6613.40
• visited https://www.nperf.com/en/ and ensured that the website wasn't working/speed test wasn't initiated
• applied --variations-pr=1180 via the QA Developer settings and restarted 1.71.5 Chromium: 128.0.6613.40
• ensured that pull/1180@58b8428788ce101b28afc318eea84c967bdf411f via brave://version under Active variations
• ensured that BraveWebcompatExceptionsServiceStudy:Enabled via brave://version
• visited https://www.nperf.com/en/ and ensured the speedtest/website was working without any issues/failures

Example	Example	Example

Nightly - min_version condition not met

Brave | 1.70.65 Chromium: 128.0.6613.27 (Official Build) canary (64-bit)
--- | ---
Revision | 8bf2d6fd36dc289a5918c6c06969c161d81717dc
OS | Android 15; Build/AP31.240617.010; 35; REL

• launched 1.70.65 Chromium: 128.0.6613.27
• visited https://www.nperf.com/en/ and ensured that the website wasn't working/speed test wasn't initiated
• applied --variations-pr=1180 via the QA Developer settings and restarted 1.70.65 Chromium: 128.0.6613.27
• ensured that pull/1180@58b8428788ce101b28afc318eea84c967bdf411f via brave://version under Active variations
• ensured that BraveWebcompatExceptionsServiceStudy:Enabled was not being displayed in brave://version
• visited https://www.nperf.com/en/ and ensured that the website wasn't working/speed test wasn't initiated

Example	Example	Example

[kjozwiak]

Uplift into production approved after deliberating with @brave/uplift-approvers 👍 QA has verified the PR on Nightly as per #1180 (comment) & #1180 (comment). QA has also verified the feature via brave/brave-browser#37074