Remove SignInSource from ShowSigninCommand.

ios/chrome/browser/signin/constants.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef IOS_CHROME_BROWSER_SIGNIN_CONSTANTS_H_
 #define IOS_CHROME_BROWSER_SIGNIN_CONSTANTS_H_
 
 #include <Foundation/Foundation.h>
 
 // Error domain for authentication error.
 extern NSString* kAuthenticationErrorDomain;
 
 // The key in the user info dictionary containing the GoogleServiceAuthError
 // code.
 extern NSString* kGoogleServiceAuthErrorState;
 
 typedef enum {
   // The error is wrapping a GoogleServiceAuthError.
   GOOGLE_SERVICE_AUTH_ERROR = -200,
   NO_AUTHENTICATED_USER = -201,
   CLIENT_ID_MISMATCH = -203,
   CLIENT_SECRET_MISMATCH = -204,
   AUTHENTICATION_FLOW_ERROR = -206,
   TIMED_OUT_FETCH_POLICY = -210,
 } AuthenticationErrorCode;
 
-// Enum is used to count the various sign in sources in the histogram
-// |Signin.IOSSignInSource|.
-typedef enum {
-  // Unspecified sign-in source. This includes sign in operations started from
-  // "Other Devices" and from the sync error infobar displayed for pre-SSO
-  // signed in users.
-  SIGN_IN_SOURCE_OTHER,
-  // Sign in operation was started from first run.
-  SIGN_IN_SOURCE_FIRST_RUN,
-  // Sign in operation was started from the SSO recall promo.
-  SIGN_IN_SOURCE_SSO_PROMO,
-  // Sign in operation was started from settings.
-  SIGN_IN_SOURCE_SETTINGS,
-  // Sign in operation was started from as a pre-requisite of share operation.
-  // Deprecated since M53.
-  SIGN_IN_SOURCE_SHARE_DEPRECATED,
-  // Sign in operation was started from as a pre-requisite of a print operation.
-  SIGN_IN_SOURCE_PRINT,
-  // Sign in operation was started from the re-sign in infobar.
-  SIGN_IN_SOURCE_RESIGN_IN_INFOBAR,
-  // Sign in operation was started from the Chrome to Device infobar.
-  SIGN_IN_SOURCE_CHROME_TO_DEVICE_INFOBAR,
-  // Sign in operation was started from the recent tabs panel.
-  SIGN_IN_SOURCE_RECENT_TABS,
-  // Sign in operation was started from the bookmarks promo panel.
-  SIGN_IN_SOURCE_BOOKMARKS_PROMO,
-  // Sign in operation was started from the Tab Switcher.
-  SIGN_IN_SOURCE_TAB_SWITCHER,
-  // NOTE: Add new sign in sources only immediately above this line. Also, make
-  // sure the enum list for histogram |Signin.IOSSignInSource| in
-  // uma/configs/chrome/histograms.xml is updated with any change in here.
-  SIGN_IN_SOURCE_COUNT
-} SignInSource;
-
 typedef enum {
   SHOULD_CLEAR_DATA_USER_CHOICE,
   SHOULD_CLEAR_DATA_CLEAR_DATA,
   SHOULD_CLEAR_DATA_MERGE_DATA,
 } ShouldClearData;
 
 // Enum is used to represent the action to be taken by the authentication once
 // the user is successfully signed in.
 typedef enum {
   POST_SIGNIN_ACTION_NONE,
   POST_SIGNIN_ACTION_START_SYNC,
 } PostSignInAction;
 
 namespace signin_ui {
 
 // Completion callback for a sign-in operation.
 // |success| is YES if the operation was successful.
 typedef void (^CompletionCallback)(BOOL success);
 
 }  // namespace signin_ui
 
 #endif  // IOS_CHROME_BROWSER_SIGNIN_CONSTANTS_H_