Consolidate EulaAcceptedNotifier implementations.

chrome/browser/metrics/variations/eula_accepted_notifier.cc

Index: chrome/browser/metrics/variations/eula_accepted_notifier.cc
===================================================================
--- chrome/browser/metrics/variations/eula_accepted_notifier.cc	(revision 203226)
+++ chrome/browser/metrics/variations/eula_accepted_notifier.cc	(working copy)
@@ -4,9 +4,14 @@
 
 #include "chrome/browser/metrics/variations/eula_accepted_notifier.h"
 
+#include "base/bind.h"
 #include "base/logging.h"
+#include "base/prefs/pref_service.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/common/pref_names.h"
 
-EulaAcceptedNotifier::EulaAcceptedNotifier() : observer_(NULL) {
+EulaAcceptedNotifier::EulaAcceptedNotifier(PrefService* local_state)
+    : local_state_(local_state), observer_(NULL) {
 }
 
 EulaAcceptedNotifier::~EulaAcceptedNotifier() {
@@ -17,13 +22,47 @@
   observer_ = observer;
 }
 
-void EulaAcceptedNotifier::NotifyObserver() {
-  observer_->OnEulaAccepted();
+bool EulaAcceptedNotifier::IsEulaAccepted() {
+  if (local_state_->GetBoolean(prefs::kEulaAccepted))
+    return true;
+
+  // Register for the notification, if this is the first time.
+  if (registrar_.IsEmpty()) {
+    registrar_.Init(local_state_);
+    registrar_.Add(prefs::kEulaAccepted,
+                   base::Bind(&EulaAcceptedNotifier::OnPrefChanged,
+                              base::Unretained(this)));
+  }
+  return false;
 }
 
-#if !defined(OS_CHROMEOS) && !defined(OS_ANDROID) && !defined(OS_IOS)
 // static
 EulaAcceptedNotifier* EulaAcceptedNotifier::Create() {
+  // First run EULA only exists on ChromeOS, Android and iOS. On ChromeOS, it is
+  // only shown in official builds.
+#if (defined(OS_CHROMEOS) && defined(GOOGLE_CHROME_BUILD)) || \
+    defined(OS_ANDROID) || defined(OS_IOS)

[SteveT, 2013/06/03 18:58:18]

optional nit: I think it would be slightly easier on the eyes if the two
"defined" keyboards were lined up here (one more space indent - I realize you
just used the standard 4).

[Alexei Svitkine (slow), 2013/06/03 20:36:38]

That would be misleading, since the defined keyword above is nested differently
(in its own set of parens), while the defined keyword below is outside those.

[SteveT, 2013/06/03 20:47:48]

Ah, you're right. SGTM.

+  PrefService* local_state = g_browser_process->local_state();
+  // Tests that use higher-level classes that use EulaAcceptNotifier may not
+  // register this pref. In this case, return NULL which is equivalent to not
+  // needing to check the EULA.
+  if (local_state->FindPreference(prefs::kEulaAccepted) == NULL)
+    return NULL;
+  return new EulaAcceptedNotifier(local_state);
+#else
   return NULL;
+#endif
 }
-#endif
+
+void EulaAcceptedNotifier::NotifyObserver() {
+  observer_->OnEulaAccepted();
+}
+
+void EulaAcceptedNotifier::OnPrefChanged() {
+  DCHECK(!registrar_.IsEmpty());
+  registrar_.RemoveAll();
+
+  DCHECK(local_state_->GetBoolean(prefs::kEulaAccepted));
+  observer_->OnEulaAccepted();
+}
+