Make mash register initial batch of accelerators in single shot.

ui/base/accelerators/accelerator_manager_delegate.h

Index: ui/base/accelerators/accelerator_manager_delegate.h
diff --git a/ui/base/accelerators/accelerator_manager_delegate.h b/ui/base/accelerators/accelerator_manager_delegate.h
index e3c6d9ccf6e53ebee773c721a1374ae0b03e18c0..d0cb811ad6d182db05f6dcc3cad81c0ddae60ef6 100644
--- a/ui/base/accelerators/accelerator_manager_delegate.h
+++ b/ui/base/accelerators/accelerator_manager_delegate.h
@@ -22,6 +22,11 @@ class UI_BASE_EXPORT AcceleratorManagerDelegate {
   // Called when there no more targets are registered for |accelerator|.
   virtual void OnAcceleratorUnregistered(const Accelerator& accelerator) = 0;
 
+  virtual void OnAcceleratorsRegistered(
+      std::vector<ui::Accelerator>& accelerators) = 0;
+  virtual void OnAcceleratorsUnregistered(
+      std::vector<ui::Accelerator>& accelerators) = 0;
+
  protected:
   virtual ~AcceleratorManagerDelegate() {}
 };