Fixes compiler warnings

Fixes compiler warnings

This patch fixes various compiler warnings: initialization order of
class members, incorrect sign comparaison, uninitialized variable,
incorrect return types, incorrect enum comparaison and incorrect type
conversions.

Bug: http://web.sec.samsung.net/bugzilla/show_bug.cgi?id=9706
Reviewed by: Antonio Gomes, SeungSeop Park

Change-Id: I6aeccb073cf9561d2cbb09c5c63e60397d81a8d1
Signed-off-by: Arnaud Renevier <a.renevier@samsung.com>