Implement newly designed sign-in related histograms for desktop platorms.

chrome/browser/ui/webui/signin/inline_login_handler.cc

Index: chrome/browser/ui/webui/signin/inline_login_handler.cc
diff --git a/chrome/browser/ui/webui/signin/inline_login_handler.cc b/chrome/browser/ui/webui/signin/inline_login_handler.cc
index f02145620f8654db225432864a203b6b2bfb16e4..6d1cea6acecc7236312b874f966d8ff6e9fe1625 100644
--- a/chrome/browser/ui/webui/signin/inline_login_handler.cc
+++ b/chrome/browser/ui/webui/signin/inline_login_handler.cc
@@ -69,17 +69,17 @@ void InlineLoginHandler::ContinueHandleInitializeMessage() {
   params.SetInteger("authMode", InlineLoginHandler::kDesktopAuthMode);
 
   const GURL& current_url = web_ui()->GetWebContents()->GetURL();
-  signin_metrics::Source source = signin::GetSourceForPromoURL(current_url);
+  signin_metrics::AccessPoint access_point =
+      signin::GetAccessPointForPromoURL(current_url);
+  signin_metrics::LogSigninAccessPointStarted(access_point);
 
-  params.SetString(
-      "continueUrl",
-      signin::GetLandingURL(signin::kSignInPromoQueryKeySource,
-                            static_cast<int>(source)).spec());
+  params.SetString("continueUrl", signin::GetLandingURL(access_point).spec());
 
   Profile* profile = Profile::FromWebUI(web_ui());
+  signin_metrics::Reason reason =
+      signin::GetSigninReasonForPromoURL(current_url);
   std::string default_email;
-  if (source != signin_metrics::SOURCE_AVATAR_BUBBLE_ADD_ACCOUNT &&
-      source != signin_metrics::SOURCE_REAUTH) {
+  if (reason == signin_metrics::REASON_SIGNIN_PRIMARY_ACCOUNT) {

[sky, 2015/12/03 22:45:28]

Isn't SOURCE_AVATAR_BUBBLE_ADD_ACCOUNT now ...SECONDARY_ACCOUNT? Is this change
intentional?

[gogerald1, 2015/12/04 20:49:09]

Yes, for other reasons there is an email key in the url. In previous code, all
the other sources are signing primary account except "ADD" and "REAUTH".

     default_email =
         profile->GetPrefs()->GetString(prefs::kGoogleServicesLastUsername);
   } else {