Remove current user requirement for VwG flow.

Author: brnnmrls

GoogleSignIn/Sources/GIDVerifyAccountDetail/Implementations/GIDVerifyAccountDetail.m

@@ -149,8 +149,6 @@ - (void)verifyAccountDetailsInteractivelyWithOptions:(GIDSignInInternalOptions *
     return;
   }
 
-  [self assertValidCurrentUser];
-
   // Explicitly throw exception for missing client ID here. This must come before
   // scheme check because schemes rely on reverse client IDs.
   [self assertValidParameters:options];
@@ -231,15 +229,6 @@ - (void)processAuthorizationResponse:(OIDAuthorizationResponse *)authorizationRe
 
 #pragma mark - Helpers
 
-// Assert that a current user exists.
-- (void)assertValidCurrentUser {
-  if (!GIDSignIn.sharedInstance.currentUser) {
-    // NOLINTNEXTLINE(google-objc-avoid-throwing-exception)
-    [NSException raise:NSInvalidArgumentException
-                format:@"|currentUser| must be set to verify."];
-  }
-}
-
 // Asserts the parameters being valid.
 - (void)assertValidParameters:(GIDSignInInternalOptions *)options {
   if (![options.configuration.clientID length]) {