Add support for //# sourceURL similar to deprecated //@ sourceURL one.

test/mjsunit/regress/regress-1853.js

Index: test/mjsunit/regress/regress-1853.js
diff --git a/test/mjsunit/regress/regress-1853.js b/test/mjsunit/regress/regress-1853.js
index f80badecb6ab94171583e3e133701634dab5cfbb..cfafe82fa35a55c978a3cdbdc24ef6e3567ffc43 100644
--- a/test/mjsunit/regress/regress-1853.js
+++ b/test/mjsunit/regress/regress-1853.js
@@ -102,13 +102,13 @@ eval('function test1() {                \n' +
      '  assertFalse(test_break_1);      \n' +
      '  assertTrue(test_break_1);       \n' +
      '}                                 \n' +
-     '//@ sourceURL=testScriptOne');
+     '//# sourceURL=testScriptOne');
 
 eval('function test2() {                \n' +
      '  assertFalse(test_break_2);      \n' +
      '  assertTrue(test_break_2);       \n' +
      '}                                 \n' +
-     '//@ sourceURL=testScriptTwo');
+     '//# sourceURL=testScriptTwo');
 
 test1();
 test2();