Do not activate TrayBubbleView by default

ash/system/palette/palette_tray.cc

Index: ash/system/palette/palette_tray.cc
diff --git a/ash/system/palette/palette_tray.cc b/ash/system/palette/palette_tray.cc
index e82b4e73dea904ed2a31469449fd835cd4dbc728..9eeca44ef12401445d568fcc2b58afb19bd0d3f3 100644
--- a/ash/system/palette/palette_tray.cc
+++ b/ash/system/palette/palette_tray.cc
@@ -4,6 +4,8 @@
 
 #include "ash/system/palette/palette_tray.h"
 
+#include "ash/accelerators/accelerator_controller.h"
+#include "ash/accessibility_delegate.h"
 #include "ash/resources/vector_icons/vector_icons.h"
 #include "ash/root_window_controller.h"
 #include "ash/session/session_controller.h"
@@ -155,7 +157,7 @@ PaletteTray::PaletteTray(Shelf* shelf)
 
 PaletteTray::~PaletteTray() {
   if (bubble_)
-    bubble_->bubble_view()->reset_delegate();
+    bubble_->bubble_view()->ResetDelegate();
 
   ui::InputDeviceManager::GetInstance()->RemoveObserver(this);
   Shell::Get()->RemoveShellObserver(this);
@@ -299,10 +301,26 @@ void PaletteTray::OnMouseEnteredView() {}
 
 void PaletteTray::OnMouseExitedView() {}
 
+void PaletteTray::RegisterAccelerators(
+    const std::vector<ui::Accelerator>& accelerators,
+    views::TrayBubbleView* tray_bubble_view) {
+  Shell::Get()->accelerator_controller()->Register(accelerators,
+                                                   tray_bubble_view);
+}
+
+void PaletteTray::UnregisterAllAccelerators(
+    views::TrayBubbleView* tray_bubble_view) {
+  Shell::Get()->accelerator_controller()->UnregisterAll(tray_bubble_view);
+}
+
 base::string16 PaletteTray::GetAccessibleNameForBubble() {
   return GetAccessibleNameForTray();
 }
 
+bool PaletteTray::ShouldEnableExtraKeyboardAccessibility() {
+  return Shell::Get()->accessibility_delegate()->IsSpokenFeedbackEnabled();
+}
+
 void PaletteTray::HideBubble(const views::TrayBubbleView* bubble_view) {
   HideBubbleWithView(bubble_view);
 }