[ubsan] Fix for vptr check

[ubsan] Fix for vptr check

Summary:
There can be a situation when vptr not initializing
by constructor of the object, and has a junk data
which should be properly checked, because c++ standard
says:

"If the new-initializer is omitted, the object is default-initialized (8.5).
[ Note: If no initialization is performed,
 the object has an indeterminate value. — end note ]

Change-Id: I6fd297dc10b2ddb54eaed9e6eb3a46310dafead4
Signed-off-by: Denis Khalikov <d.khalikov@partner.samsung.com>