Add window cycle completion and cancellation accelerators in mus+ash.

ui/base/accelerators/accelerator.h

Index: ui/base/accelerators/accelerator.h
diff --git a/ui/base/accelerators/accelerator.h b/ui/base/accelerators/accelerator.h
index 57956a18c6ee308e756d1a8400d591476f3dc399..f5ee41709ccf41896dd6f2c49ebe26d79c0fa52d 100644
--- a/ui/base/accelerators/accelerator.h
+++ b/ui/base/accelerators/accelerator.h
@@ -42,7 +42,9 @@ class UI_BASE_EXPORT Accelerator {
 
   Accelerator();
   // NOTE: this constructor strips out non key related flags.
-  Accelerator(KeyboardCode key_code, int modifiers);
+  Accelerator(KeyboardCode key_code,
+              int modifiers,
+              KeyState key_state = KeyState::PRESSED);
   explicit Accelerator(const KeyEvent& key_event);
   Accelerator(const Accelerator& accelerator);
   ~Accelerator();