add coercion tests and fix a bug in String.prototype.trim() testcase
add coercion tests and fix a bug in String.prototype.trim() testcase

reqshark/duktape,daimajia/duktape,nivertech/duktape,markand/duktape,chenyaqiuqiu/duktape,jmptrader/duktape,haosu1987/duktape,sloth4413/duktape,tassmjau/duktape,jmptrader/duktape,chenyaqiuqiu/duktape,rwaldron/duktape,harold-b/duktape,markand/duktape,kphillisjr/duktape,thurday/duktape,skomski/duktape,chenyaqiuqiu/duktape,jmptrader/duktape,harold-b/duktape,markand/duktape,skomski/duktape,zeropool/duktape,reqshark/duktape,rwaldron/duktape,jmptrader/duktape,chenyaqiuqiu/duktape,reqshark/duktape,nivertech/duktape,markand/duktape,kphillisjr/duktape,jmptrader/duktape,harold-b/duktape,pombredanne/duktape,sloth4413/duktape,rwaldron/duktape,eddieh/duktape,zeropool/duktape,pombredanne/duktape,tassmjau/duktape,eddieh/duktape,sloth4413/duktape,harold-b/duktape,chenyaqiuqiu/duktape,eddieh/duktape,haosu1987/duktape,skomski/duktape,thurday/duktape,haosu1987/duktape,svaarala/duktape,kphillisjr/duktape,nivertech/duktape,tassmjau/duktape,reqshark/duktape,zeropool/duktape,svaarala/duktape,kphillisjr/duktape,tassmjau/duktape,svaarala/duktape,eddieh/duktape,nivertech/duktape,kphillisjr/duktape,skomski/duktape,eddieh/duktape,haosu1987/duktape,markand/duktape,sloth4413/duktape,svaarala/duktape,harold-b/duktape,daimajia/duktape,kphillisjr/duktape,thurday/duktape,tassmjau/duktape,svaarala/duktape,kphillisjr/duktape,pombredanne/duktape,chenyaqiuqiu/duktape,skomski/duktape,reqshark/duktape,thurday/duktape,tassmjau/duktape,nivertech/duktape,jmptrader/duktape,svaarala/duktape,sloth4413/duktape,tassmjau/duktape,svaarala/duktape,zeropool/duktape,zeropool/duktape,thurday/duktape,jmptrader/duktape,markand/duktape,sloth4413/duktape,nivertech/duktape,eddieh/duktape,kphillisjr/duktape,skomski/duktape,nivertech/duktape,harold-b/duktape,haosu1987/duktape,jmptrader/duktape,haosu1987/duktape,chenyaqiuqiu/duktape,markand/duktape,thurday/duktape,skomski/duktape,sloth4413/duktape,zeropool/duktape,pombredanne/duktape,reqshark/duktape,markand/duktape,zeropool/duktape,haosu1987/duktape,pombredanne/duktape,daimajia/duktape,thurday/duktape,zeropool/duktape,sloth4413/duktape,kphillisjr/duktape,daimajia/duktape,skomski/duktape,harold-b/duktape,rwaldron/duktape,tassmjau/duktape,thurday/duktape,reqshark/duktape,haosu1987/duktape,markand/duktape,nivertech/duktape,svaarala/duktape,thurday/duktape,pombredanne/duktape,thurday/duktape,sloth4413/duktape,reqshark/duktape,skomski/duktape,reqshark/duktape,eddieh/duktape,jmptrader/duktape,skomski/duktape,chenyaqiuqiu/duktape,nivertech/duktape,rwaldron/duktape,svaarala/duktape,haosu1987/duktape,pombredanne/duktape,eddieh/duktape,sloth4413/duktape,kphillisjr/duktape,tassmjau/duktape,daimajia/duktape,tassmjau/duktape,chenyaqiuqiu/duktape,eddieh/duktape,pombredanne/duktape,harold-b/duktape,reqshark/duktape,markand/duktape,nivertech/duktape,harold-b/duktape,harold-b/duktape,zeropool/duktape,pombredanne/duktape,rwaldron/duktape,chenyaqiuqiu/duktape,eddieh/duktape,daimajia/duktape,haosu1987/duktape,jmptrader/duktape,pombredanne/duktape,zeropool/duktape