Revert of Do not activate TrayBubbleView by default

ash/system/tray/system_tray.cc

Index: ash/system/tray/system_tray.cc
diff --git a/ash/system/tray/system_tray.cc b/ash/system/tray/system_tray.cc
index d129fba629f271ca16bda49ec0d24a31ae84667f..66ca2527aa0a3fcbdf222f0f1912912471c14af7 100644
--- a/ash/system/tray/system_tray.cc
+++ b/ash/system/tray/system_tray.cc
@@ -8,7 +8,6 @@
 #include <map>
 #include <vector>
 
-#include "ash/accelerators/accelerator_controller.h"
 #include "ash/key_event_watcher.h"
 #include "ash/login_status.h"
 #include "ash/public/cpp/config.h"
@@ -119,14 +118,19 @@
                 TrayBubbleView::InitParams* init_params,
                 bool is_persistent) {
     DCHECK(anchor);
-
-    is_persistent_ = is_persistent;
-
     const LoginStatus login_status =
         Shell::Get()->session_controller()->login_status();
     bubble_->InitView(anchor, login_status, init_params);
     bubble_->bubble_view()->set_anchor_view_insets(anchor_insets);
     bubble_wrapper_.reset(new TrayBubbleWrapper(tray, bubble_->bubble_view()));
+    is_persistent_ = is_persistent;
+
+    // If ChromeVox is enabled, focus the default item if no item is focused and
+    // there isn't a delayed close.
+    if (Shell::Get()->accessibility_delegate()->IsSpokenFeedbackEnabled() &&
+        !is_persistent) {
+      bubble_->FocusDefaultIfNeeded();
+    }
   }
 
   // Convenience accessors:
@@ -206,6 +210,7 @@
 SystemTray::~SystemTray() {
   // Destroy any child views that might have back pointers before ~View().
   activation_observer_.reset();
+  key_event_watcher_.reset();
   system_bubble_.reset();
   for (const auto& item : items_)
     item->OnTrayViewDestroyed();
@@ -432,6 +437,9 @@
 
   if (system_bubble_.get() && creation_type == BUBBLE_USE_EXISTING) {
     system_bubble_->bubble()->UpdateView(items, bubble_type);
+    // If ChromeVox is enabled, focus the default item if no item is focused.
+    if (Shell::Get()->accessibility_delegate()->IsSpokenFeedbackEnabled())
+      system_bubble_->bubble()->FocusDefaultIfNeeded();
   } else {
     // Cleanup the existing bubble before showing a new one. Otherwise, it's
     // possible to confuse the new system bubble with the old one during
@@ -449,6 +457,8 @@
     init_params.anchor_alignment = GetAnchorAlignment();
     init_params.min_width = kTrayMenuMinimumWidth;
     init_params.max_width = kTrayPopupMaxWidth;
+    // TODO(oshima): Change TrayBubbleView itself.
+    init_params.can_activate = false;
     // The bubble is not initially activatable, but will become activatable if
     // the user presses Tab. For behavioral consistency with the non-activatable
     // scenario, don't close on deactivation after Tab either.
@@ -477,6 +487,10 @@
   if (!detailed)
     default_bubble_height_ = system_bubble_->bubble_view()->height();
 
+  key_event_watcher_.reset();
+  if (can_activate)
+    CreateKeyEventWatcher();
+
   if (detailed && items.size() > 0)
     detailed_item_ = items[0];
   else
@@ -567,28 +581,8 @@
     system_bubble_->bubble()->RestartAutoCloseTimer();
 }
 
-void SystemTray::RegisterAccelerators(
-    const std::vector<ui::Accelerator>& accelerators,
-    views::TrayBubbleView* tray_bubble_view) {
-  Shell::Get()->accelerator_controller()->Register(accelerators,
-                                                   tray_bubble_view);
-}
-
-void SystemTray::UnregisterAllAccelerators(
-    views::TrayBubbleView* tray_bubble_view) {
-  Shell::Get()->accelerator_controller()->UnregisterAll(tray_bubble_view);
-}
-
 base::string16 SystemTray::GetAccessibleNameForBubble() {
   return GetAccessibleNameForTray();
-}
-
-bool SystemTray::ShouldEnableExtraKeyboardAccessibility() {
-  // Do not enable extra keyboard accessibility for persistent system bubble.
-  // e.g. volume slider. Persistent system bubble is a bubble which is not
-  // closed even if user clicks outside of the bubble.
-  return system_bubble_ && !system_bubble_->is_persistent() &&
-         Shell::Get()->accessibility_delegate()->IsSpokenFeedbackEnabled();
 }
 
 void SystemTray::HideBubble(const TrayBubbleView* bubble_view) {
@@ -606,6 +600,24 @@
 
   views::Widget* widget = GetSystemBubble()->bubble_view()->GetWidget();
   widget->GetFocusManager()->OnKeyEvent(key_event);
+}
+
+void SystemTray::CreateKeyEventWatcher() {
+  key_event_watcher_ = ShellPort::Get()->CreateKeyEventWatcher();
+  // mustash does not yet support KeyEventWatcher. http://crbug.com/649600.
+  if (!key_event_watcher_)
+    return;
+  key_event_watcher_->AddKeyEventCallback(
+      ui::Accelerator(ui::VKEY_ESCAPE, ui::EF_NONE),
+      base::Bind(&SystemTray::CloseBubble, base::Unretained(this)));
+  key_event_watcher_->AddKeyEventCallback(
+      ui::Accelerator(ui::VKEY_TAB, ui::EF_NONE),
+      base::Bind(&SystemTray::ActivateAndStartNavigation,
+                 base::Unretained(this)));
+  key_event_watcher_->AddKeyEventCallback(
+      ui::Accelerator(ui::VKEY_TAB, ui::EF_SHIFT_DOWN),
+      base::Bind(&SystemTray::ActivateAndStartNavigation,
+                 base::Unretained(this)));
 }
 
 void SystemTray::ActivateBubble() {
@@ -635,6 +647,7 @@
 
 void SystemTray::CloseSystemBubbleAndDeactivateSystemTray() {
   activation_observer_.reset();
+  key_event_watcher_.reset();
   system_bubble_.reset();
   // When closing a system bubble with the alternate shelf layout, we need to
   // turn off the active tinting of the shelf.