Update notification icon color when session types change.

Prevents showing the notification icon being invisible, or in a faded
color in certain conditions.

- Faded color after first sign-in (crbug.com/880766)
After OOBE is finished, the icon color should be updated.

- Invisible do-not-disturb icon in OOBE (crbug.com/886561)
Session status is UNKNOWN at the view creation during OOBE.

Bug: 880766,886561
Change-Id: I82d22a5d0967ab9c0fdef3b109ea3157e0244d8c
Reviewed-on: https://chromium-review.googlesource.com/1233101Reviewed-by: Yoshiki Iguchi <yoshiki@chromium.org>
Commit-Queue: Tatsuhisa Yamaguchi <yamaguchi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593107}

ash/system/unified/notification_counter_view.cc

@@ -89,10 +89,13 @@ class NumberIconImageSource : public gfx::CanvasImageSource {
 
 NotificationCounterView::NotificationCounterView() : TrayItemView(nullptr) {
   CreateImageView();
-  Update();
+  SetVisible(false);
+  Shell::Get()->session_controller()->AddObserver(this);
 }
 
-NotificationCounterView::~NotificationCounterView() = default;
+NotificationCounterView::~NotificationCounterView() {
+  Shell::Get()->session_controller()->RemoveObserver(this);
+}
 
 void NotificationCounterView::Update() {
   size_t notification_count =
@@ -111,22 +114,38 @@ void NotificationCounterView::Update() {
   SetVisible(true);
 }
 
+void NotificationCounterView::OnSessionStateChanged(
+    session_manager::SessionState state) {
+  Update();
+}
+
 QuietModeView::QuietModeView() : TrayItemView(nullptr) {
   CreateImageView();
+  SetVisible(false);
+  Shell::Get()->session_controller()->AddObserver(this);
+}
+
+QuietModeView::~QuietModeView() {
+  Shell::Get()->session_controller()->RemoveObserver(this);
+}
+
+void QuietModeView::Update() {
   // TODO(yamaguchi): Add this check when new style of the system tray is
   // implemented, so that icon resizing will not happen here.
   // DCHECK_EQ(kTrayIconSize,
   //     gfx::GetDefaultSizeOfVectorIcon(kSystemTrayDoNotDisturbIcon));
+  if (message_center::MessageCenter::Get()->IsQuietMode()) {
     image_view()->SetImage(gfx::CreateVectorIcon(
         kSystemTrayDoNotDisturbIcon,
         TrayIconColor(Shell::Get()->session_controller()->GetSessionState())));
-  Update();
+    SetVisible(true);
+  } else {
+    SetVisible(false);
+  }
 }
 
-QuietModeView::~QuietModeView() = default;
-
-void QuietModeView::Update() {
-  SetVisible(message_center::MessageCenter::Get()->IsQuietMode());
+void QuietModeView::OnSessionStateChanged(session_manager::SessionState state) {
+  Update();
 }
 
 }  // namespace ash

ash/system/unified/notification_counter_view.h

@@ -5,19 +5,23 @@
 #ifndef ASH_SYSTEM_UNIFIED_NOTIFICATION_COUNTER_VIEW_H_
 #define ASH_SYSTEM_UNIFIED_NOTIFICATION_COUNTER_VIEW_H_
 
+#include "ash/session/session_observer.h"
 #include "ash/system/tray/tray_item_view.h"
 #include "base/macros.h"
 
 namespace ash {
 
 // A notification counter view in UnifiedSystemTray button.
-class NotificationCounterView : public TrayItemView {
+class NotificationCounterView : public TrayItemView, public SessionObserver {
  public:
   NotificationCounterView();
   ~NotificationCounterView() override;
 
   void Update();
 
+  // SessionObserver:
+  void OnSessionStateChanged(session_manager::SessionState state) override;
+
  private:
   // The type / number of the icon that is currently set to the image view.
   // 0 indicates no icon is drawn yet.
@@ -29,13 +33,16 @@ class NotificationCounterView : public TrayItemView {
 };
 
 // A do-not-distrub icon view in UnifiedSystemTray button.
-class QuietModeView : public TrayItemView {
+class QuietModeView : public TrayItemView, public SessionObserver {
  public:
   QuietModeView();
   ~QuietModeView() override;
 
   void Update();
 
+  // SessionObserver:
+  void OnSessionStateChanged(session_manager::SessionState state) override;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(QuietModeView);
 };