Do not activate system tray bubble by default

ash/common/system/chromeos/tray_caps_lock.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/common/system/chromeos/tray_caps_lock.h"
 
 #include "ash/common/material_design/material_design_controller.h"
 #include "ash/common/system/tray/actionable_view.h"
 #include "ash/common/system/tray/fixed_sized_image_view.h"
 #include "ash/common/system/tray/system_tray_delegate.h"
@@ skipping 22 matching lines @@
       chromeos::input_method::InputMethodManager::Get();
   return (ime && ime->GetImeKeyboard())
              ? ime->GetImeKeyboard()->CapsLockIsEnabled()
              : false;
 }
 }
 
 class CapsLockDefaultView : public ActionableView {
  public:
   CapsLockDefaultView()
-      : text_label_(new views::Label), shortcut_label_(new views::Label) {
+      : ActionableView(nullptr),
+        text_label_(new views::Label),
+        shortcut_label_(new views::Label) {
     SetLayoutManager(new views::BoxLayout(views::BoxLayout::kHorizontal,
                                           kTrayPopupPaddingHorizontal, 0,
                                           kTrayPopupPaddingBetweenItems));
 
     FixedSizedImageView* image =
         new FixedSizedImageView(0, GetTrayConstant(TRAY_POPUP_ITEM_HEIGHT));
     if (MaterialDesignController::UseMaterialDesignSystemIcons()) {
       image->SetImage(
           gfx::CreateVectorIcon(kSystemMenuCapsLockIcon, kMenuIconColor));
     } else {
@@ skipping 168 matching lines @@
 
 void TrayCapsLock::DestroyDefaultView() {
   default_ = NULL;
 }
 
 void TrayCapsLock::DestroyDetailedView() {
   detailed_ = NULL;
 }
 
 }  // namespace ash