exo: Fix dragging edge cases

components/exo/keyboard.h

Index: components/exo/keyboard.h
diff --git a/components/exo/keyboard.h b/components/exo/keyboard.h
index b56834fca6c09f088a2cfb7f56ac86e5989a005e..ed184dfd01d6368cfd764154403bd85ea5e6866d 100644
--- a/components/exo/keyboard.h
+++ b/components/exo/keyboard.h
@@ -27,7 +27,7 @@ class Surface;
 class Keyboard : public ui::EventHandler,
                  public WMHelper::FocusObserver,
                  public WMHelper::InputDeviceEventObserver,
-                 public WMHelper::MaximizeModeObserver,
+                 public WMHelper::ShellObserver,
                  public SurfaceObserver {
  public:
   explicit Keyboard(KeyboardDelegate* delegate);
@@ -50,7 +50,7 @@ class Keyboard : public ui::EventHandler,
   // Overridden from ui::InputDeviceEventObserver:
   void OnKeyboardDeviceConfigurationChanged() override;
 
-  // Overridden from WMHelper::MaximizeModeObserver:
+  // Overridden from WMHelper::ShellObserver:
   void OnMaximizeModeStarted() override;
   void OnMaximizeModeEnded() override;