Fix stale keyboard bounds on login screen

ui/keyboard/keyboard_controller.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 "ui/keyboard/keyboard_controller.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "content/public/browser/render_widget_host.h"
 #include "content/public/browser/render_widget_host_iterator.h"
@@ skipping 287 matching lines @@
               view->SetInsets(gfx::Insets(0, 0, overlap, 0));
             else
               view->SetInsets(gfx::Insets());
             AddBoundsChangedObserver(window);
           }
         }
       }
     } else {
       ResetWindowInsets();
     }
+  } else {
+    current_keyboard_bounds_ = gfx::Rect();
   }
 }
 
 void KeyboardController::HideKeyboard(HideReason reason) {
   keyboard_visible_ = false;
   ToggleTouchEventLogging(true);
 
   keyboard::LogKeyboardControlEvent(
       reason == HIDE_REASON_AUTOMATIC ?
           keyboard::KEYBOARD_CONTROL_HIDE_AUTO :
@@ skipping 228 matching lines @@
 
 void KeyboardController::RemoveBoundsChangedObserver(aura::Window* window) {
   aura::Window* target_window = GetFrameWindow(window);
   if (target_window &&
       target_window->HasObserver(window_bounds_observer_.get())) {
     target_window->RemoveObserver(window_bounds_observer_.get());
   }
 }
 
 }  // namespace keyboard