Fix crash when AccessibilityManager called when profile is nullptr

chrome/browser/chromeos/accessibility/accessibility_manager.cc

 // Copyright (c) 2013 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 "chrome/browser/chromeos/accessibility/accessibility_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 580 matching lines @@
   if (cl->HasSwitch(kAshDisableSystemSounds))
     return false;
   if (option == PlaySoundOption::SPOKEN_FEEDBACK_ENABLED &&
       !IsSpokenFeedbackEnabled() && !cl->HasSwitch(kAshEnableSystemSounds)) {
     return false;
   }
   return media::SoundsManager::Get()->Play(sound_key);
 }
 
 void AccessibilityManager::OnTwoFingerTouchStart() {
+  if (!profile())

[oshima, 2017/05/02 01:45:20]

optional: just noticed that all other places are using profile_. I'm fine as is
though.

+    return;
+
   extensions::EventRouter* event_router =
       extensions::EventRouter::Get(profile());
   CHECK(event_router);
 
   auto event_args = base::MakeUnique<base::ListValue>();
   auto event = base::MakeUnique<extensions::Event>(
       extensions::events::ACCESSIBILITY_PRIVATE_ON_TWO_FINGER_TOUCH_START,
       extensions::api::accessibility_private::OnTwoFingerTouchStart::kEventName,
       std::move(event_args));
   event_router->BroadcastEvent(std::move(event));
 }
 
 void AccessibilityManager::OnTwoFingerTouchStop() {
+  if (!profile())
+    return;
+
   extensions::EventRouter* event_router =
       extensions::EventRouter::Get(profile());
   CHECK(event_router);
 
   auto event_args = base::MakeUnique<base::ListValue>();
   auto event = base::MakeUnique<extensions::Event>(
       extensions::events::ACCESSIBILITY_PRIVATE_ON_TWO_FINGER_TOUCH_STOP,
       extensions::api::accessibility_private::OnTwoFingerTouchStop::kEventName,
       std::move(event_args));
   event_router->BroadcastEvent(std::move(event));
@@ skipping 906 matching lines @@
     content::BrowserContext* context) {
   keyboard_listener_extension_id_ = id;
 
   extensions::ExtensionRegistry* registry =
       extensions::ExtensionRegistry::Get(context);
   if (!extension_registry_observer_.IsObserving(registry) && !id.empty())
     extension_registry_observer_.Add(registry);
 }
 
 }  // namespace chromeos