Adding Finch and flag for Sign-in promo

ios/chrome/browser/about_flags.mm

 // Copyright 2012 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.
 
 // Implementation of about_flags for iOS that sets flags based on experimental
 // settings.
 
 #include "ios/chrome/browser/about_flags.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #import <UIKit/UIKit.h>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/singleton.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/sys_info.h"
 #include "base/task_scheduler/switches.h"
 #include "components/dom_distiller/core/dom_distiller_switches.h"
 #include "components/flags_ui/feature_entry.h"
 #include "components/flags_ui/feature_entry_macros.h"
 #include "components/flags_ui/flags_storage.h"
 #include "components/flags_ui/flags_ui_switches.h"
 #include "components/ntp_tiles/switches.h"
 #include "components/reading_list/core/reading_list_switches.h"
+#include "components/signin/core/common/signin_switches.h"
 #include "components/strings/grit/components_strings.h"
 #include "ios/chrome/browser/chrome_switches.h"
 #include "ios/chrome/grit/ios_strings.h"
 #include "ios/public/provider/chrome/browser/chrome_browser_provider.h"
 #include "ios/web/public/user_agent.h"
 #include "ios/web/public/web_view_creation_util.h"
 
 #if !defined(OFFICIAL_BUILD)
 #include "components/variations/variations_switches.h"
 #endif
@@ skipping 184 matching lines @@
       NSString* flag = [defaults stringForKey:key];
       if ([flag length]) {
         flags.push_back(base::SysNSStringToUTF8(flag));
       }
     }
 
     base::CommandLine temp_command_line(flags);
     command_line->AppendArguments(temp_command_line, false);
   }
 
+  // Populate command line flag for Suggestions UI display.

[msarda, 2017/03/29 11:41:35]

s/Suggestions UI/Sign-in promo

[jlebel, 2017/03/29 11:47:08]

Done.

+  NSString* enableSigninPromo = [defaults stringForKey:@"EnableSigninPromo"];
+  if ([enableSigninPromo isEqualToString:@"Enabled"]) {
+    command_line->AppendSwitch(switches::kEnableSigninPromo);
+  } else if ([enableSigninPromo isEqualToString:@"Disabled"]) {
+    command_line->AppendSwitch(switches::kDisableSigninPromo);
+  }
+
   ios::GetChromeBrowserProvider()->AppendSwitchesFromExperimentalSettings(
       defaults, command_line);
 }
 
 bool SkipConditionalFeatureEntry(const flags_ui::FeatureEntry& entry) {
   return false;
 }
 
 class FlagsStateSingleton {
  public:
@@ skipping 52 matching lines @@
 }
 
 namespace testing {
 
 const flags_ui::FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing