Fixed C/C++ interworking problem in IAndroidEffect

Fixed C/C++ interworking problem in IAndroidEffect

The IAndroidEffect structure contains a KeyedVector object
which constructor was not called when the structure was allocated.

The fix consists in changing the structure member to a pointer
to a KeyedVector and create the object from C++ code when the
object containing the IAndroidInterface is created (AudioPlayer
and OutputMix).

Change-Id: I328b4b61537ddb178b33427c6bad06678a29647a