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 d69ead118f5b8531c642c99d7b192ad33f9c0c13..f6d23c32992430f82400e5f0ce3198b4b574f163 100644
--- a/ui/aura_shell/desktop_event_filter.cc
+++ b/ui/aura_shell/desktop_event_filter.cc
@@ -8,6 +8,7 @@
 #include "ui/aura/event.h"
 #include "ui/aura/focus_manager.h"
 #include "ui/aura/window_delegate.h"
+#include "ui/aura_shell/global_accelerator_filter.h"
 #include "ui/aura_shell/shell.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()),
+      global_accelerator_filter_(new GlobalAcceleratorFilter) {
+  AddFilter(global_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(global_accelerator_filter_.get());
 }
 
 void DesktopEventFilter::AddFilter(aura::EventFilter* filter) {