A11y: Add the option to always show the a11y tray menu regardless of the state of a11y features

Change summary:
- Add 'const' to ShellDelegate::IsUserLoggedIn()
- Use TrayImageItem::UpdateAfterLoginStatusChange delegate instead of ShellObserver::OnLoginStateChanged()
- Add a pref: kShouldAlwaysShowAccessibilityMenu
- Add a checkbox to chrome://settings

BUG=158287
TEST=manual

Review URL: https://chromiumcodereview.appspot.com/11280236

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@170732 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 4 deletions

diff --git a/ash/shell/shell_delegate_impl.cc b/ash/shell/shell_delegate_impl.cc
index 1d569c8..1edc9d1 100644
--- a/ash/shell/shell_delegate_impl.cc
+++ b/ash/shell/shell_delegate_impl.cc
@@ -36,19 +36,19 @@ void ShellDelegateImpl::SetWatcher(WindowWatcher* watcher) {
     launcher_delegate_->set_watcher(watcher);
 }
 
-bool ShellDelegateImpl::IsUserLoggedIn() {
+bool ShellDelegateImpl::IsUserLoggedIn() const {
   return true;
 }
 
-bool ShellDelegateImpl::IsSessionStarted() {
+bool ShellDelegateImpl::IsSessionStarted() const {
   return true;
 }
 
-bool ShellDelegateImpl::IsFirstRunAfterBoot() {
+bool ShellDelegateImpl::IsFirstRunAfterBoot() const {
   return false;
 }
 
-bool ShellDelegateImpl::CanLockScreen() {
+bool ShellDelegateImpl::CanLockScreen() const {
   return true;
 }