Implement new password separated sign in flow for chrome desktop.

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 1f3e2c72da9bb08b97ecbb5f438a060e805a2419..e20571cba7fe958a59333437016b2b61fa6b3ee4 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -1374,6 +1374,12 @@ const Experiment kExperiments[] = {
      IDS_FLAGS_ENABLE_IFRAME_BASED_SIGNIN_DESCRIPTION,
      kOsMac | kOsWin | kOsLinux,
      SINGLE_VALUE_TYPE(switches::kEnableIframeBasedSignin)},
+    {"enable-password-separated-signin-flow",
+     IDS_FLAGS_ENABLE_PASSWORD_SEPARATED_SIGNIN_FLOW_NAME,
+     IDS_FLAGS_ENABLE_PASSWORD_SEPARATED_SIGNIN_FLOW_DESCRIPTION,
+     kOsWin | kOsLinux,
+     ENABLE_DISABLE_VALUE_TYPE(switches::kEnablePasswordSeparatedSigninFlow,
+                               switches::kDisablePasswordSeparatedSigninFlow)},
     {"enable-google-profile-info",
      IDS_FLAGS_ENABLE_GOOGLE_PROFILE_INFO_NAME,
      IDS_FLAGS_ENABLE_GOOGLE_PROFILE_INFO_DESCRIPTION,