Move views::Accelerator to ui in order to use it from aura code.

views/window/dialog_client_view.cc

Index: views/window/dialog_client_view.cc
diff --git a/views/window/dialog_client_view.cc b/views/window/dialog_client_view.cc
index 3dbea55b035e78affa533d9811e69f815e8cbbcf..1fbed2b4919ee40f8190dce091ee6cf62c3ace20 100644
--- a/views/window/dialog_client_view.cc
+++ b/views/window/dialog_client_view.cc
@@ -77,7 +77,7 @@ class DialogButton : public NativeTextButton {
   }
 
   // Overridden to forward to the delegate.
-  virtual bool AcceleratorPressed(const Accelerator& accelerator) {
+  virtual bool AcceleratorPressed(const ui::Accelerator& accelerator) {
     if (!owner_->widget_delegate()->AsDialogDelegate()->
         AreAcceleratorsEnabled(type_)) {
       return false;
@@ -402,7 +402,7 @@ gfx::Size DialogClientView::GetPreferredSize() {
   return prefsize;
 }
 
-bool DialogClientView::AcceleratorPressed(const Accelerator& accelerator) {
+bool DialogClientView::AcceleratorPressed(const ui::Accelerator& accelerator) {
   // We only expect Escape key.
   DCHECK(accelerator.key_code() == ui::VKEY_ESCAPE);
   Close();