Need to release CropView when destroy WallpaperCrop Activity

When we use default Gallery to set Wallpaper several times.
wallpapercropper process will crash caused by OOM.
So we need to call mCropView.destroy() to destroy TextureView
in CropView when WallpaperCropActivity try to destroy.

Change-Id: I211ff32da3ec02f148d4a9d437d57d93b07bc6f3
Signed-off-by: jshe32X<jianchunx.shen@intel.com>
view: make setWallpaperPosition() oneway

It is possible that live wallpaper can sleep or too busy
when setWallpaperPosition is called from the launcher.
This can block the launcher process and make launcher to
operate slowly as well. One way to fix this problem is
making setWallpaperPostion() oneway so the launcher
process does not wait for live-wallpaper process

Change-Id: Ifd98ec89945f554d5c53590aa264fb452cc77f23
OptiPNG
-o7 -zm1-9