Refactor string literal test for parsers

Thsi test for the parsing of string literals was expressed using `eval`.
This made the test more complex than necessary and also prevented the
test from providing value to ECMAScript parsers.

Remove the use of `eval` and instead express the expectation with
literal source text.

test/language/literals/string/legacy-octal-escape-sequence-prologue-strict.js

@@ -6,9 +6,14 @@ es5id: 7.8.4-1-s
 description: >
     A directive preceeding an 'use strict' directive may not contain
     an OctalEscapeSequence
+negative:
+  phase: parse
+  type: SyntaxError
 ---*/
 
-
-assert.throws(SyntaxError, function() {
-    eval(' "asterisk: \\052" /* octal escape sequences forbidden in strict mode*/ ; "use strict";');
+throw "Test262: This statement should not be evaluated.";
+
+(function() {
+  "asterisk: \052";
+  "use strict";
 });