Move functions for controlling Caps Lock to CapsLockDelegate from SystemTrayDelegate.

ash/caps_lock_delegate.h

Index: ash/caps_lock_delegate.h
diff --git a/ash/caps_lock_delegate.h b/ash/caps_lock_delegate.h
index 158457dba54bb7060b7249bd4c5f9d8d0d133368..b792f77c1b5326e589af2fc540f606e9fd9a23eb 100644
--- a/ash/caps_lock_delegate.h
+++ b/ash/caps_lock_delegate.h
@@ -5,17 +5,25 @@
 #ifndef ASH_CAPS_LOCK_DELEGATE_H_
 #define ASH_CAPS_LOCK_DELEGATE_H_
 
+#include "ash/ash_export.h"
+
 namespace ash {
 
-// Delegate for toggling Caps Lock.
-class CapsLockDelegate {
+// Delegate for controlling Caps Lock.
+class ASH_EXPORT CapsLockDelegate {
  public:
   virtual ~CapsLockDelegate() {}
 
-  // A derived class should do either of the following: 1) toggle Caps Lock and
-  // return true, or 2) do nothing and return false (see crosbug.com/110127).
-  virtual bool HandleToggleCapsLock() = 0;
+  // Returns true if the caps lock is enabled.

[Daniel Erat, 2012/08/27 17:26:57]

nit: s/the caps lock/caps lock/

[mazda, 2012/08/27 21:07:49]

Done.

+  virtual bool IsCapsLockEnabled() const = 0;
+
+  // Sets the caps lock state to |enabled|.
+  virtual void SetCapsLockEnabled(bool enabled) = 0;

[Daniel Erat, 2012/08/27 17:26:57]

document that this method and ToggleCapsLock() toggle the state asynchronously,
and calls to IsCapsLockEnabled() just after these may return the old state?  or
is it safe to update CapsLockHandler::caps_lock_is_on_ from these methods so
that the new state is shown immediately?

[mazda, 2012/08/27 21:07:49]

Currently pressing caps lock key is handled separately in SystemKeyEventListener
without calling these functions, so I think it's better not to set
caps_lock_is_on_ in the place other than OnCapsLockChagned to avoid the state
gets inconsistent state.
I added the note on the asynchronous state change.

+
+  // Toggles the caps lock state.
+  virtual void ToggleCapsLock() = 0;
 };
+
 }  // namespace ash
 
 #endif  // ASH_CAPS_LOCK_DELEGATE_H_