Introduce reauthenticateUserWithID:email:callback:

ios/public/provider/chrome/browser/signin/chrome_identity_interaction_manager.h

Index: ios/public/provider/chrome/browser/signin/chrome_identity_interaction_manager.h
diff --git a/ios/public/provider/chrome/browser/signin/chrome_identity_interaction_manager.h b/ios/public/provider/chrome/browser/signin/chrome_identity_interaction_manager.h
index ccbb66d748505983ff2a2bd4307a37844704dbee..a12b31b3b5ffe370ea4132e8f2202eb403ddc020 100644
--- a/ios/public/provider/chrome/browser/signin/chrome_identity_interaction_manager.h
+++ b/ios/public/provider/chrome/browser/signin/chrome_identity_interaction_manager.h
@@ -50,6 +50,18 @@ typedef void (^SigninCompletionCallback)(ChromeIdentity* identity,
 // Note: Calling this method will fail and the completion will be called with a
 // CHROME_IDENTITY_OPERATION_ONGOING error if there is already another add
 // account or reauthenticate operation ongoing.
+// * |userID| is the unique identifier of the user.
+// * |userEmail| will be pre-entered on the presented screen.
+// * |completion| will be called once the operation has finished.
+- (void)reauthenticateUserWithID:(NSString*)userID
+                           email:(NSString*)userEmail
+                      completion:(SigninCompletionCallback)completion;
+
+// Starts the reauthentication operation for a user. Presents user with the
+// screen to enter credentials with the email pre-entered.
+// Note: Calling this method will fail and the completion will be called with a
+// CHROME_IDENTITY_OPERATION_ONGOING error if there is already another add
+// account or reauthenticate operation ongoing.
 // * |email| will be pre-entered on the presented screen.
 // * |completion| will be called once the operation has finished.
 - (void)reauthenticateUserWithEmail:(NSString*)email