Create stand-alone json parser (including scanner).

src/factory.cc

Index: src/factory.cc
===================================================================
--- src/factory.cc	(revision 7898)
+++ src/factory.cc	(working copy)
@@ -111,12 +111,25 @@
                      String);
 }
 
+
 Handle<String> Factory::LookupAsciiSymbol(Vector<const char> string) {
   CALL_HEAP_FUNCTION(isolate(),
                      isolate()->heap()->LookupAsciiSymbol(string),
                      String);
 }
 
+
+Handle<String> Factory::LookupAsciiSymbol(Handle<SeqAsciiString> string,
+                                          int from,
+                                          int length) {
+  CALL_HEAP_FUNCTION(isolate(),
+                     isolate()->heap()->LookupAsciiSymbol(string,
+                                                          from,
+                                                          length),
+                     String);
+}
+
+
 Handle<String> Factory::LookupTwoByteSymbol(Vector<const uc16> string) {
   CALL_HEAP_FUNCTION(isolate(),
                      isolate()->heap()->LookupTwoByteSymbol(string),