Support global keyboard commands on Chrome OS.

ash/accelerators/accelerator_controller.h

Index: ash/accelerators/accelerator_controller.h
diff --git a/ash/accelerators/accelerator_controller.h b/ash/accelerators/accelerator_controller.h
index 374286e50dd15b9c637cbfd84d5fe8d832aceddf..0cf77fbe84b74a290d88fc671f20b3b1da55ebb4 100644
--- a/ash/accelerators/accelerator_controller.h
+++ b/ash/accelerators/accelerator_controller.h
@@ -38,6 +38,19 @@ class ASH_EXPORT AcceleratorController : public ui::AcceleratorTarget {
   AcceleratorController();
   virtual ~AcceleratorController();
 
+  // A list of possible ways in which an accelerator should be restricted before
+  // processing.

[Finnur, 2014/06/26 10:37:35]

I think we should flesh out this comment a little more, as in why are we doing
this and whether the restriction is global (applies to everything or limited to
some targets).

[David Tseng, 2014/06/27 00:49:11]

It is a non-enforced restriction at the moment.

Any target registered with AcceleratorController should respect the restriction,
but it is currently only enforced by each target.

Unfortunately, the class isn't well flushed out because it also acts as an
AcceleratorTarget; at some point, we should break up the class, but I don't
think that's within scope of this cl?

I left a better comment.

+  enum AcceleratorProcessRestriction {

[Finnur, 2014/06/26 10:37:35]

nit: Process is ambiguous. Processing?

[David Tseng, 2014/06/27 00:49:10]

Yup :); getting wordy, but it does make more sense.

+    // Process the accelerator normally.
+    RESTRICTION_NONE,
+
+    // Don't process the accelerator.
+    RESTRICTION_PREVENT_PROCESSING,
+
+    // Don't process the accelerator and prevent propagation to other targets.
+    RESTRICTION_PREVENT_PROCESSING_AND_PROPAGATION
+  };
+
   // Registers a global keyboard accelerator for the specified target. If
   // multiple targets are registered for an accelerator, a target registered
   // later has higher priority.
@@ -71,6 +84,11 @@ class ASH_EXPORT AcceleratorController : public ui::AcceleratorTarget {
   bool PerformAction(int action,
                      const ui::Accelerator& accelerator);
 
+  // Gets any restriction for the given accelerator and action.

[Finnur, 2014/06/26 10:37:35]

nit: "Returns which restriction applies to a given ..."

[David Tseng, 2014/06/27 00:49:11]

Done.

+  AcceleratorProcessRestriction GetAcceleratorProcessRestriction(

[Finnur, 2014/06/26 10:37:35]

ditto: Ambiguous word "Process".

[David Tseng, 2014/06/27 00:49:10]

Done, everywhere.

+      int action,
+      ui::Accelerator accelerator);

[Finnur, 2014/06/26 10:37:35]

const ui::Accelerator& ?

[David Tseng, 2014/06/27 00:49:10]

Done.

+
   // Overridden from ui::AcceleratorTarget:
   virtual bool AcceleratorPressed(const ui::Accelerator& accelerator) OVERRIDE;
   virtual bool CanHandleAccelerators() const OVERRIDE;