Add ShellAcceleratorController that managers global keyboard accelerators.

ui/aura_shell/desktop_event_filter.cc

Index: ui/aura_shell/desktop_event_filter.cc
diff --git a/ui/aura_shell/desktop_event_filter.cc b/ui/aura_shell/desktop_event_filter.cc
index dc4b4cf0ff47458fc16902ca2c431da09eabd4b2..67a75ea779e1ebfa3e85da5c6d676af897214b82 100644
--- a/ui/aura_shell/desktop_event_filter.cc
+++ b/ui/aura_shell/desktop_event_filter.cc
@@ -9,6 +9,7 @@
 #include "ui/aura/focus_manager.h"
 #include "ui/aura/window_delegate.h"
 #include "ui/aura_shell/shell.h"
+#include "ui/aura_shell/shell_accelerator_filter.h"
 #include "ui/aura_shell/stacking_controller.h"
 #include "ui/base/hit_test.h"
 
@@ -43,13 +44,16 @@ gfx::NativeCursor CursorForWindowComponent(int window_component) {
 // DesktopEventFilter, public:
 
 DesktopEventFilter::DesktopEventFilter()
-    : EventFilter(aura::Desktop::GetInstance()) {
+    : EventFilter(aura::Desktop::GetInstance()),
+      shell_accelerator_filter_(new ShellAcceleratorFilter) {
+  AddFilter(shell_accelerator_filter_.get());
 }
 
 DesktopEventFilter::~DesktopEventFilter() {
   // Additional filters are not owned by DesktopEventFilter and they
   // should all be removed when running here. |filters_| has
   // check_empty == true and will DCHECK failure if it is not empty.
+  RemoveFilter(shell_accelerator_filter_.get());
 }
 
 void DesktopEventFilter::AddFilter(aura::EventFilter* filter) {