Introduce FakeChromeIdentity and FakeChromeIdentityService.

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

Index: ios/public/provider/chrome/browser/signin/fake_chrome_identity_service.h
diff --git a/ios/public/provider/chrome/browser/signin/fake_chrome_identity_service.h b/ios/public/provider/chrome/browser/signin/fake_chrome_identity_service.h
new file mode 100644
index 0000000000000000000000000000000000000000..7e225f5e1aa75ede0366d237009e6613b5cfef07
--- /dev/null
+++ b/ios/public/provider/chrome/browser/signin/fake_chrome_identity_service.h
@@ -0,0 +1,63 @@
+// Copyright 2016 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_PUBLIC_PROVIDER_CHROME_BROWSER_SIGNIN_FAKE_CHROME_IDENTITY_SERVICE_H_
+#define IOS_PUBLIC_PROVIDER_CHROME_BROWSER_SIGNIN_FAKE_CHROME_IDENTITY_SERVICE_H_
+
+#include "ios/public/provider/chrome/browser/signin/chrome_identity_service.h"
+
+#include "base/mac/scoped_nsobject.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+@class NSMutableArray;
+
+namespace ios {
+
+// A fake ChromeIdentityService used for testing.
+class FakeChromeIdentityService : public ChromeIdentityService {
+ public:
+  FakeChromeIdentityService();
+  ~FakeChromeIdentityService();
+
+  // Returns the instance of |FakeChromeIdentityService|.
+  static FakeChromeIdentityService* GetInstance();

[msarda, 2016/07/07 11:58:06]

When I see a static method name GetInstance, I think that this will return a
global instance of type FakeChromeIdentityService. This makes me think there is
a single instance of this variable for all the tests, which is bad.

I think it would be better to remove this method and make each test that needs
this method instantiate its own FakeChromeIdentityService.

If you prefer to keep it, please rename it to match the implementation (like
GetInstanceFromChromeProvider) and explain what it does in a comment.

[bzanotti, 2016/07/07 12:48:11]

Renamed to GetInstanceFromChromeProvider. Instantiating there own
FakeChromeIdentityService is already possible and is *NOT* what should be done
generally.

+
+  // ChromeIdentityService implementation.
+  bool IsValidIdentity(ChromeIdentity* identity) const override;
+  ChromeIdentity* GetIdentityWithEmail(const std::string& email) const override;
+  ChromeIdentity* GetIdentityWithGaiaID(
+      const std::string& gaia_id) const override;
+  bool HasIdentities() const override;
+  NSArray* GetAllIdentities() const override;
+  NSArray* GetAllIdentitiesSortedForDisplay() const override;
+  void ForgetIdentity(ChromeIdentity* identity,
+                      ForgetIdentityCallback callback) override;
+
+  MOCK_METHOD5(GetAccessToken,
+               void(ChromeIdentity* identity,
+                    const std::string& client_id,
+                    const std::string& client_secret,
+                    const std::set<std::string>& scopes,
+                    const ios::AccessTokenCallback& callback));
+
+  MOCK_METHOD1(GetMDMDeviceStatus,
+               ios::MDMDeviceStatus(NSDictionary* user_info));
+
+  MOCK_METHOD3(HandleMDMNotification,
+               bool(ChromeIdentity* identity,
+                    NSDictionary* user_info,
+                    ios::MDMStatusCallback callback));
+
+  // Adds the identities given their name.
+  void AddIdentities(NSArray* identitiesNames);
+
+  // Adds |identity| to the available identities.
+  void AddIdentity(ChromeIdentity* identity);
+
+ private:
+  base::scoped_nsobject<NSMutableArray> identities_;
+};
+}
+
+#endif  // IOS_PUBLIC_PROVIDER_CHROME_BROWSER_SIGNIN_FAKE_CHROME_IDENTITY_SERVICE_H_