Remove MutableProfileOAuth2TokenService on iOS.

ios/public/test/fake_profile_oauth2_token_service_ios_provider.mm

 // 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.
 
 #include "ios/public/test/fake_profile_oauth2_token_service_ios_provider.h"
 
 #include <Foundation/Foundation.h>
 
 #include "base/logging.h"
 #include "base/strings/sys_string_conversions.h"
 
 namespace ios {
 
 FakeProfileOAuth2TokenServiceIOSProvider::
-    FakeProfileOAuth2TokenServiceIOSProvider()
-    : is_using_shared_authentication_(true) {}
+    FakeProfileOAuth2TokenServiceIOSProvider() {}
 
 FakeProfileOAuth2TokenServiceIOSProvider::
     ~FakeProfileOAuth2TokenServiceIOSProvider() {}
 
 void FakeProfileOAuth2TokenServiceIOSProvider::GetAccessToken(
     const std::string& account_id,
     const std::string& client_id,
     const std::string& client_secret,
     const std::set<std::string>& scopes,
     const AccessTokenCallback& callback) {
-  DCHECK(is_using_shared_authentication_);
   requests_.push_back(AccessTokenRequest(account_id, callback));
 }
 
 std::vector<std::string>
 FakeProfileOAuth2TokenServiceIOSProvider::GetAllAccountIds() {
   return accounts_;
 }
 
 void FakeProfileOAuth2TokenServiceIOSProvider::AddAccount(
     const std::string& account_id) {
@@ skipping 28 matching lines @@
     std::string account_id = i->first;
     AccessTokenCallback callback = i->second;
     NSError* error = [[[NSError alloc] initWithDomain:@"fake_access_token_error"
                                                  code:-1
                                              userInfo:nil] autorelease];
     callback.Run(nil, nil, error);
   }
   requests_.clear();
 }
 
-bool FakeProfileOAuth2TokenServiceIOSProvider::IsUsingSharedAuthentication()
-    const {
-  return is_using_shared_authentication_;
-}
-
 void
 FakeProfileOAuth2TokenServiceIOSProvider::InitializeSharedAuthentication() {}
 
 AuthenticationErrorCategory
 FakeProfileOAuth2TokenServiceIOSProvider::GetAuthenticationErrorCategory(
     NSError* error) const {
   DCHECK(error);
   return ios::kAuthenticationErrorCategoryAuthorizationErrors;
 }
 
 }  // namespace ios