Removed unused methods from |SigninMetrics|.

Change-Id: Ib32c1f08beb81fbfd721d9e45a1a576a68721f30
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1826780Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Commit-Queue: Matthias Körber <koerber@google.com>
Cr-Commit-Position: refs/heads/master@{#700191}

components/signin/public/base/signin_metrics.cc

@@ -742,11 +742,6 @@ void LogAuthError(const GoogleServiceAuthError& auth_error) {
   }
 }
 
-void LogSigninConfirmHistogramValue(ConfirmationUsage action) {
-  UMA_HISTOGRAM_ENUMERATION("Signin.OneClickConfirmation", action,
-                            HISTOGRAM_CONFIRM_MAX);
-}
-
 void LogAccountReconcilorStateOnGaiaResponse(AccountReconcilorState state) {
   UMA_HISTOGRAM_ENUMERATION("Signin.AccountReconcilorState.OnGaiaResponse",
                             state, ACCOUNT_RECONCILOR_HISTOGRAM_COUNT);

components/signin/public/base/signin_metrics.h

@@ -378,8 +378,6 @@ void LogExternalCcResultFetches(
 // Track when the current authentication error changed.
 void LogAuthError(const GoogleServiceAuthError& auth_error);
 
-void LogSigninConfirmHistogramValue(ConfirmationUsage action);
-
 // Records the AccountReconcilor |state| when GAIA returns a specific response.
 // If |state| is different than ACCOUNT_RECONCILOR_OK it means the user will
 // be shown a different set of accounts in the content-area and the settings UI.