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 c2892723973c52261cfe3f4f3d802b1188feb469..55056b3141303e51e56bec59bc0a897c6f663662 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -1353,6 +1353,12 @@ 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,