Improved key-input focus manager performance

Improved key-input focus manager performance

[model]        KIRAN
[binary_type]  Lite
[customer]     OPEN
[issue#]       N/A
[problem]      KeyInput focus manager uses actor ID's and traverses the
entire actor tree for all focus methods.
[cause]        Bad programming
[solution]     Changed stack to use BaseObject pointers. Track object lifetime
using the registry (Controls are automatically registered).
[team]         Graphics
[request]      N/A
[horizontal_expansion]  N/A

Change-Id: I4e49f0ca5adb990a71bedb8a4b5e6c08114db43c
Signed-off-by: David Steele <david.steele@partner.samsung.com>