Experimental lexer generator: Add test files.

test/cornercases/end-inside-string.js

Index: test/cornercases/end-inside-string.js
diff --git a/test/mjsunit/regress/regress-173361.js b/test/cornercases/end-inside-string.js
similarity index 95%
copy from test/mjsunit/regress/regress-173361.js
copy to test/cornercases/end-inside-string.js
index f9cfb6684c0d52996c7ceac8412defbaf48a5eeb..625a4d6bfe1f20b5fd76863210b69ad2a4c584b8 100644
--- a/test/mjsunit/regress/regress-173361.js
+++ b/test/cornercases/end-inside-string.js
@@ -25,9 +25,4 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --harmony
-
-const x = 7;
-
-function f() { const y = 8; }
-f();
+var description = "this file ends inside a string -- that can't be good!