Add a11y on-screen keyboard to accessibility menu on system tray.

chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc

Index: chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
diff --git a/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc b/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
index e567dfbd8342cb0de29f313e1983dd646b00bf4f..11c5ee9b7a83c7b4ac5aaeef7f5b78a3e6b0ca76 100644
--- a/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
+++ b/chrome/browser/ui/ash/chrome_shell_delegate_chromeos.cc
@@ -119,6 +119,12 @@ class AccessibilityDelegateImpl : public ash::AccessibilityDelegate {
     return chromeos::AccessibilityManager::Get()->IsAutoclickEnabled();
   }
 
+  virtual void SetVirtualKeyboardEnabled(bool enabled) OVERRIDE {
+    DCHECK(chromeos::AccessibilityManager::Get());
+    return chromeos::AccessibilityManager::Get()->
+        EnableVirtualKeyboard(enabled);
+  }
+
   virtual bool IsVirtualKeyboardEnabled() const OVERRIDE {
     DCHECK(chromeos::AccessibilityManager::Get());
     return chromeos::AccessibilityManager::Get()->IsVirtualKeyboardEnabled();