value: Add some positive testcase for string deserialization
value: Add some positive testcase for string deserialization

shelsonjava/gstreamer,jpxiong/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,surround-io/gstreamer,centricular/gstreamer,jpxiong/gstreamer,shelsonjava/gstreamer,Lachann/gstreamer,mparis/gstreamer,surround-io/gstreamer,shelsonjava/gstreamer,shelsonjava/gstreamer,mparis/gstreamer,mparis/gstreamer,surround-io/gstreamer,Lachann/gstreamer,krichter722/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,StreamUtils/gstreamer,krichter722/gstreamer,krichter722/gstreamer,jpakkane/gstreamer,Lachann/gstreamer,surround-io/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,Lachann/gstreamer,centricular/gstreamer,jpakkane/gstreamer,centricular/gstreamer,jpxiong/gstreamer,mparis/gstreamer,jpakkane/gstreamer,surround-io/gstreamer,Lachann/gstreamer,mparis/gstreamer,jpakkane/gstreamer,jpakkane/gstreamer,centricular/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,centricular/gstreamer,shelsonjava/gstreamer