Introduce FakeChromeIdentity and FakeChromeIdentityService.

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

+// 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.
+
+#import "ios/public/provider/chrome/browser/signin/fake_chrome_identity_service.h"
+
+#import <Foundation/Foundation.h>
+
+#include "base/strings/sys_string_conversions.h"
+#include "ios/public/provider/chrome/browser/chrome_browser_provider.h"
+#import "ios/public/provider/chrome/browser/signin/fake_chrome_identity.h"
+
+namespace ios {
+
+NSString* const kIdentityEmailFormat = @"%@@foo.com";
+NSString* const kIdentityGaiaIDFormat = @"%@ID";
+
+FakeChromeIdentityService::FakeChromeIdentityService()
+    : identities_([[NSMutableArray alloc] init]) {}
+
+FakeChromeIdentityService::~FakeChromeIdentityService() {}
+
+// static
+FakeChromeIdentityService* FakeChromeIdentityService::GetInstance() {
+  return static_cast<ios::FakeChromeIdentityService*>(
+      ios::GetChromeBrowserProvider()->GetChromeIdentityService());
+}
+
+bool FakeChromeIdentityService::IsValidIdentity(
+    ChromeIdentity* identity) const {
+  return [identities_ indexOfObject:identity] != NSNotFound;
+}
+
+ChromeIdentity* FakeChromeIdentityService::GetIdentityWithEmail(
+    const std::string& email) const {
+  NSString* userEmail = base::SysUTF8ToNSString(email);
+  NSUInteger index =
+      [identities_ indexOfObjectPassingTest:^BOOL(ChromeIdentity* obj,
+                                                  NSUInteger, BOOL* stop) {
+        return [[obj userEmail] isEqualToString:userEmail];

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

In general, emails need to be sanitized and canonicalized before comparing them.

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

Good point, but this was causing some dependencies pain.

I removed the method anyway because we don't want to fake this method, we
actually want to remove it altogether (getting an identity via an email should
go through the AccountTrackerService to get the gaia ID).

+      }];
+  if (index == NSNotFound) {
+    return nil;
+  }
+  return [identities_ objectAtIndex:index];
+}
+
+ChromeIdentity* FakeChromeIdentityService::GetIdentityWithGaiaID(
+    const std::string& gaia_id) const {
+  NSString* gaiaID = base::SysUTF8ToNSString(gaia_id);
+  NSUInteger index =
+      [identities_ indexOfObjectPassingTest:^BOOL(ChromeIdentity* obj,
+                                                  NSUInteger, BOOL* stop) {
+        return [[obj gaiaID] isEqualToString:gaiaID];
+      }];
+  if (index == NSNotFound) {
+    return nil;
+  }
+  return [identities_ objectAtIndex:index];
+}
+
+bool FakeChromeIdentityService::HasIdentities() const {
+  return [identities_ count] > 0;
+}
+
+NSArray* FakeChromeIdentityService::GetAllIdentities() const {
+  return identities_;
+}
+
+NSArray* FakeChromeIdentityService::GetAllIdentitiesSortedForDisplay() const {
+  return identities_;
+}
+
+void FakeChromeIdentityService::ForgetIdentity(
+    ChromeIdentity* identity,
+    ForgetIdentityCallback callback) {
+  [identities_ removeObject:identity];
+  FireIdentityListChanged();
+  if (callback) {

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

I think we should use the Chromium style of posting task on the main loop (using
POST_TASK). Then the test can run the message loop using the same syntax as all
the rest of the Chromium code.

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

The RunLoop already support the iOS dispatch mechanism.

+    dispatch_async(dispatch_get_main_queue(), ^{

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

Why do we dispatch here. Wouldn't it be easier to just call the callback
synchronously?

[sdefresne, 2016/07/07 12:12:40]

+1, please add a comment explaining why if it cannot be synchronous.

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

Added a comment here. Basically, ForgetIdentity is an asynchronous operation, so
I think it's better when testing to enforce this.

+      callback(nil);
+    });
+  }
+}
+
+void FakeChromeIdentityService::AddIdentities(NSArray* identitiesNames) {
+  for (NSString* name in identitiesNames) {
+    NSString* email = [NSString stringWithFormat:kIdentityEmailFormat, name];
+    NSString* gaiaID = [NSString stringWithFormat:kIdentityGaiaIDFormat, name];
+    [identities_ addObject:[FakeChromeIdentity identityWithEmail:email
+                                                          gaiaID:gaiaID
+                                                            name:name]];
+  }
+}
+
+void FakeChromeIdentityService::AddIdentity(ChromeIdentity* identity) {
+  [identities_ addObject:identity];
+  FireIdentityListChanged();
+}
+}

[sdefresne, 2016/07/07 12:12:40]

}  // namespace ios

and add a blank line before

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

Done.

+