Pin keyboard works with virtual keyboard.

chrome/browser/chromeos/login/lock/webui_screen_locker.cc

 // Copyright 2014 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/login/lock/webui_screen_locker.h"
 
 #include "ash/common/wm_shell.h"
 #include "ash/shell.h"
 #include "ash/system/chromeos/power/power_event_observer.h"
 #include "base/command_line.h"
@@ skipping 355 matching lines @@
   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // keyboard::KeyboardControllerObserver:
 
 void WebUIScreenLocker::OnKeyboardBoundsChanging(
     const gfx::Rect& new_bounds) {
   if (new_bounds.IsEmpty()) {
     // Keyboard has been hidden.
-    if (GetOobeUI())
+    if (GetOobeUI()) {
       GetOobeUI()->GetCoreOobeActor()->ShowControlBar(true);
+      GetOobeUI()->GetCoreOobeActor()->ShowPinKeyboard(true);
+    }
   } else {
     // Keyboard has been shown.
-    if (GetOobeUI())
+    if (GetOobeUI()) {
       GetOobeUI()->GetCoreOobeActor()->ShowControlBar(false);
+      GetOobeUI()->GetCoreOobeActor()->ShowPinKeyboard(false);
+    }
   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // display::DisplayObserver:
 
 void WebUIScreenLocker::OnDisplayAdded(const display::Display& new_display) {}
 
 void WebUIScreenLocker::OnDisplayRemoved(const display::Display& old_display) {}
 
 void WebUIScreenLocker::OnDisplayMetricsChanged(const display::Display& display,
                                                 uint32_t changed_metrics) {
   display::Display primary_display =
       display::Screen::GetScreen()->GetPrimaryDisplay();
   if (display.id() != primary_display.id() ||
       !(changed_metrics & DISPLAY_METRIC_BOUNDS)) {
     return;
   }
 
   if (GetOobeUI()) {
     const gfx::Size& size = primary_display.size();
     GetOobeUI()->GetCoreOobeActor()->SetClientAreaSize(size.width(),
                                                        size.height());
   }
 }
 
 }  // namespace chromeos