Add test case for line continuation

test/mocha/string-literal.js

@@ -14,16 +14,21 @@ describe("String literals", function() {
         var test = function(input) {
             return function() {
                 var ast = UglifyJS.parse(input);
-            }
+            };
         };
 
         var error = function(e) {
             return e instanceof UglifyJS.JS_Parse_Error &&
-                e.message === "Unterminated string constant"
+                e.message === "Unterminated string constant";
         };
 
         for (var input in inputs) {
             assert.throws(test(inputs[input]), error);
         }
     });
+
+    it("Should not throw syntax error if a string has a line continuation", function() {
+        var output = UglifyJS.parse('var a = "a\\\nb";').print_to_string();
+        assert.equal(output, 'var a="ab";');
+    });
 });