Hook up new API for easy unlock to update lock screen

chrome/browser/signin/easy_unlock_service.cc

Index: chrome/browser/signin/easy_unlock_service.cc
diff --git a/chrome/browser/signin/easy_unlock_service.cc b/chrome/browser/signin/easy_unlock_service.cc
index 1afcbc9e128e45c78b357f083d75025b091eac08..3a093a1d3bbad7b0eeaaffd2dc4c8ea233945eac 100644
--- a/chrome/browser/signin/easy_unlock_service.cc
+++ b/chrome/browser/signin/easy_unlock_service.cc
@@ -13,7 +13,9 @@
 #include "chrome/browser/extensions/component_loader.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/signin/easy_unlock_screenlock_state_handler.h"
 #include "chrome/browser/signin/easy_unlock_service_factory.h"
+#include "chrome/browser/signin/screenlock_bridge.h"
 #include "chrome/browser/ui/extensions/application_launch.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
@@ -45,7 +47,12 @@ EasyUnlockService* EasyUnlockService::Get(Profile* profile) {
 }
 
 EasyUnlockService::EasyUnlockService(Profile* profile)
-    : profile_(profile), weak_ptr_factory_(this) {
+    : profile_(profile),
+      screenlock_state_handler_(new EasyUnlockScreenlockStateHandler(
+          ScreenlockBridge::GetAuthenticatedUserEmail(profile),

[xiyuan, 2014/08/12 18:09:47]

EasyUnlockService is created with profile. Authenticated user name might not be
there when this gets called. We probably should defer
|screenlock_state_handler_| construction or make it get the user email when
needed.

[tbarzic, 2014/08/12 19:14:36]

Done. Now creating |screenlock_state_handler_| lazily.

[dzhioev (left Google), 2014/08/12 19:36:09]

Confirm. Authenticated user name definitely is not set at this point on first
login. Moreover it is never set for any user type expect regular users. Probably
we shouldn't create service for such users at all, or choose another way to
obtain user_id.

[tbarzic, 2014/08/12 21:40:58]

OK, changed the app loading logic to allow the app only for regular users and
bound screenlock_state_handler_ lifetime to easy unlock app's (between LoadApp
and UnloadApp).

(AuthenticatesUserEmail should be set by the time extension system is
initialized, right?)

[dzhioev (left Google), 2014/08/13 15:43:19]

I'm not sure, but I would not rely on it.
Why do you use authenticated username in the first place? On CrOS reliable
source of user's email is a User object, which can be gotten from profile with
ProfileHelper::GetUserByProfile method.

[xiyuan, 2014/08/13 15:53:41]

Tony has changed to lazily create |screenlock_state_handler_| in last patch so
that it does not depends on the extension system. And when it is called,
everything should already be up and running.

Easy unlock is not chrome os specific and we might support that in desktop
Mirror as well. That's why we have ScreenlockBridge::GetAuthenticatedUserEmail
wrapper. If we should stick with User on ChromeOS, we can change the wrapper
impl.

+          profile->GetPrefs(),
+          ScreenlockBridge::Get())),
+      weak_ptr_factory_(this) {
   extensions::ExtensionSystem::Get(profile_)->ready().Post(
       FROM_HERE,
       base::Bind(&EasyUnlockService::Initialize,