[Enrollment v2] Enable CryptAuth v2 Enrollment

CryptAuth v2 Enrollment has been rolling out since early January and
all metrics looks good. Enabling by default on ToT.

Canary/Dev/Beta 50% Stable 75%: cl/303637582
Canary/Dev/Beta 50% Stable 50%: cl/302902204
Canary/Dev/Beta 50% Stable 25%: cl/301402506
Canary/Dev/Beta 50% Stable 10%: cl/299940266
Canary/Dev/Beta 50% Stable 1% : cl/297128969
Canary/Dev/Beta 50% Stable 0% : cl/290773644
Canary/Dev      50% Stable 0% : cl/288753213

Fixed: 899080
Change-Id: I28a15e004f2dec0f9f4229721f065c83cba78b96
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2127517
Commit-Queue: Josh Nohle <nohle@chromium.org>
Commit-Queue: James Vecore <vecore@google.com>
Auto-Submit: Josh Nohle <nohle@chromium.org>
Reviewed-by: James Vecore <vecore@google.com>
Cr-Commit-Position: refs/heads/master@{#756703}

chromeos/constants/chromeos_features.cc

@@ -118,7 +118,7 @@ const base::Feature kCryptAuthV2DeviceSync{"CryptAuthV2DeviceSync",
 
 // Enables or disables the CryptAuth v2 Enrollment flow.
 const base::Feature kCryptAuthV2Enrollment{"CryptAuthV2Enrollment",
-                                           base::FEATURE_DISABLED_BY_DEFAULT};
+                                           base::FEATURE_ENABLED_BY_DEFAULT};
 
 // Disables the CryptAuth v1 DeviceSync flow. Note: During the first phase
 // of the v2 DeviceSync rollout, v1 and v2 DeviceSync run in parallel. This flag