cros: Nuke features::kQuickUnlockPin

It's been enabled for a long time

Bug: 935613
Change-Id: I5aef1f2f797859fa855756276139a0d94bb82397
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2339336
Auto-Submit: Roman Sorokin [CET] <rsorokin@chromium.org>
Commit-Queue: Renato Silva <rrsilva@google.com>
Reviewed-by: Renato Silva <rrsilva@google.com>
Cr-Commit-Position: refs/heads/master@{#795042}

chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.cc

@@ -113,8 +113,7 @@ bool IsPinEnabled(PrefService* pref_service) {
   if (user && user->GetType() == user_manager::UserType::USER_TYPE_SUPERVISED)
     return false;
 
-  // Enable quick unlock only if the switch is present.
-  return base::FeatureList::IsEnabled(features::kQuickUnlockPin);
+  return true;
 }
 
 // Returns fingerprint location depending on the commandline switch.

chrome/common/chrome_features.cc

@@ -693,11 +693,6 @@ const base::Feature kUserActivityEventLogging{"UserActivityEventLogging",
 #endif
 
 #if defined(OS_CHROMEOS)
-// Enables or disables pin quick unlock.
-// TODO(https://crbug.com/935613): Remove this & the backing code.
-const base::Feature kQuickUnlockPin{"QuickUnlockPin",
-                                    base::FEATURE_ENABLED_BY_DEFAULT};
-
 // Controls whether the PIN auto submit feature is enabled.
 const base::Feature kQuickUnlockPinAutosubmit{
     "QuickUnlockPinAutosubmit", base::FEATURE_DISABLED_BY_DEFAULT};

chrome/common/chrome_features.h

@@ -455,8 +455,6 @@ extern const base::Feature kUserActivityEventLogging;
 #endif
 
 #if defined(OS_CHROMEOS)
-COMPONENT_EXPORT(CHROME_FEATURES) extern const base::Feature kQuickUnlockPin;
-
 COMPONENT_EXPORT(CHROME_FEATURES)
 extern const base::Feature kQuickUnlockPinAutosubmit;