Restore screen work area after login

ui/keyboard/keyboard_controller_proxy.h

Index: ui/keyboard/keyboard_controller_proxy.h
diff --git a/ui/keyboard/keyboard_controller_proxy.h b/ui/keyboard/keyboard_controller_proxy.h
index de4473e05695d043a63192edbb9e8f33f3122dfe..e9c0118f6cbe135a4772b5306aae7e73da91f327 100644
--- a/ui/keyboard/keyboard_controller_proxy.h
+++ b/ui/keyboard/keyboard_controller_proxy.h
@@ -44,6 +44,10 @@ class KEYBOARD_EXPORT KeyboardControllerProxy {
   // Whether the keyboard window is resizing from its web contents.
   bool resizing_from_contents() const { return resizing_from_contents_; }
 
+  // Whether the keyboard window is created. The keyboard window is tied to a
+  // WebContent so we can just check if the WebContent is created or not.
+  bool HasKeyboardWindow() const { return keyboard_contents_; }
+
   // Sets the flag of whether the keyboard window is resizing from
   // its web contents.
   void set_resizing_from_contents(bool resizing) {