[iOS][MICe] Update default sign-in title in Settings.

Promote Sync as the default option in Settings. This will make the
Settings terminology more consistent with following sign-in flow
screens.

Screenshot: https://drive.google.com/file/d/1CHdPdbjJ1ppB_TakOcB4JuiQtoJW3-ld

Bug: 1151289
Change-Id: Ia053d6c07874d22ab4b77395d40140305b9dffc0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2627375Reviewed-by: Jérôme Lebel <jlebel@chromium.org>
Commit-Queue: Nohemi Fernandez <fernandex@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843999}

ios/chrome/app/strings/ios_strings.grd

@@ -186,6 +186,9 @@ locale.  The strings in this file are specific to iOS.
       <message name="IDS_IOS_ACCOUNT_UNIFIED_CONSENT_TITLE" desc="Title on the sync consent dialog to explain why sync can be useful for the user. [iOS only]">
         Turn on sync?
       </message>
+      <message name="IDS_IOS_SYNC_PROMO_TURN_ON_SYNC" desc="Button that the user can press if they want to turn on sync with this account. [iOS only]">
+        Turn on sync
+      </message>
       <message name="IDS_IOS_ACCOUNT_UNIFIED_CONSENT_SYNC_TITLE" desc="Title of the sync description section on the sync consent dialog to explain why sync can be useful for the user. [iOS only]">
         Sync your passwords, history &amp; more on all devices
       </message>

ios/chrome/app/strings/ios_strings_grd/IDS_IOS_SYNC_PROMO_TURN_ON_SYNC.png.sha1

+1e426c38c6e1eab64b60941e7bc5a59c10e11adc
\ No newline at end of file

ios/chrome/browser/ui/settings/cells/BUILD.gn

@@ -37,6 +37,7 @@ source_set("cells") {
   deps = [
     ":public",
     "//components/autofill/core/browser",
+    "//components/signin/public/base",
     "//components/strings",
     "//ios/chrome/app/strings",
     "//ios/chrome/browser/browsing_data",

ios/chrome/browser/ui/settings/cells/account_sign_in_item.mm

@@ -4,10 +4,13 @@
 
 #import "ios/chrome/browser/ui/settings/cells/account_sign_in_item.h"
 
+#include "base/feature_list.h"
+#include "components/signin/public/base/account_consistency_method.h"
 #import "ios/chrome/browser/ui/settings/cells/settings_image_detail_text_cell.h"
 #import "ios/chrome/browser/ui/settings/settings_table_view_controller_constants.h"
 #import "ios/chrome/browser/ui/util/uikit_ui_util.h"
 #include "ios/chrome/grit/ios_chromium_strings.h"
+#include "ios/chrome/grit/ios_strings.h"
 #include "ios/public/provider/chrome/browser/chrome_browser_provider.h"
 #include "ios/public/provider/chrome/browser/signin/signin_resources_provider.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -32,8 +35,14 @@
 - (void)configureCell:(SettingsImageDetailTextCell*)cell
            withStyler:(ChromeTableViewStyler*)styler {
   [super configureCell:cell withStyler:styler];
+  if (base::FeatureList::IsEnabled(signin::kMobileIdentityConsistency)) {
+    cell.textLabel.text =
+        l10n_util::GetNSString(IDS_IOS_SYNC_PROMO_TURN_ON_SYNC);
+  } else {
     cell.textLabel.text =
         l10n_util::GetNSString(IDS_IOS_SIGN_IN_TO_CHROME_SETTING_TITLE);
+  }
+
   cell.detailTextLabel.text = self.detailText;
   cell.image = CircularImageFromImage(ios::GetChromeBrowserProvider()
                                           ->GetSigninResourcesProvider()