fix for MOSYNC-2873 ImagePickerTest crashes on Android if you check the "return image data with the event" option

- a fix in the runtime -> made sure that the bitmap exists and hasn't
already been recycled before recycling
- the main fix: the ImagePickerTest where the image placeholder was
being destroyed while the image was active (i.e. displayed)
amended fix for MOSYNC-2645
fix for warnings in MoSyncThread.jave

+ replaced new Integer(intValue) with the recommended
Integer.valueOf(intValue)
Integer.valueOf() no longer necessary in some places

as of lately Java compiler can take care of ints
Merge pull request #484 from chovus/ThreeThreeOne

ImagePickerTest crashes on Android