Replaced \xA0 by \u00A0 in the whitespace definition in the metagrammar.

This is purely stylistic change.

lib/metagrammar.pegjs

@@ -209,4 +209,4 @@ eolChar: [\n\r\u2028\u2029]
  * Modelled after ECMA-262, 5th ed., 7.2. \uFEFF should be between the
  * characters too, but it causes infinite loop in Rhino.
  */
-whitespace "whitespace": [ \t\v\f\xA0\u1680\u180E\u2000-\u200A\u202F\u205F\u3000]
+whitespace "whitespace": [ \t\v\f\u00A0\u1680\u180E\u2000-\u200A\u202F\u205F\u3000]

test/metagrammar-test.js

@@ -433,7 +433,7 @@ with (PEG.Grammar) {
     grammarParserParses('start:\v"abcd"',     simpleGrammar);
     grammarParserParses('start:\f"abcd"',     simpleGrammar);
     grammarParserParses('start: "abcd"',      simpleGrammar);
-    grammarParserParses('start:\xA0"abcd"',   simpleGrammar);
+    grammarParserParses('start:\u00A0"abcd"', simpleGrammar);
     grammarParserParses('start:\u1680"abcd"', simpleGrammar);
     grammarParserParses('start:\u180E"abcd"', simpleGrammar);
     grammarParserParses('start:\u2000"abcd"', simpleGrammar);