Extract scanner base/JS/JSON and move base and JS to scanner-base.

src/parser.h

Index: src/parser.h
diff --git a/src/parser.h b/src/parser.h
index 64f621c9e2e695d8e24f690b1ce07ca73adc3676..e15a7fac441f5b9f930a607ea78c0c987342fa0c 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -682,7 +682,7 @@ class Parser {
   Expression* ParseV8Intrinsic(bool* ok);
 
   INLINE(Token::Value peek()) { return scanner_.peek(); }
-  INLINE(Token::Value Next()) { return scanner_.Next(); }
+  INLINE(Token::Value Next()) { return scanner_.NextCheckStack(); }
   INLINE(void Consume(Token::Value token));
   void Expect(Token::Value token, bool* ok);
   bool Check(Token::Value token);
@@ -760,7 +760,7 @@ class Parser {
   ZoneList<Handle<String> > symbol_cache_;
 
   Handle<Script> script_;
-  Scanner scanner_;
+  V8JavaScriptScanner scanner_;
 
   Scope* top_scope_;
   int with_nesting_level_;
@@ -852,7 +852,7 @@ class JsonParser BASE_EMBEDDED {
   // Converts the currently parsed literal to a JavaScript String.
   Handle<String> GetString();
 
-  Scanner scanner_;
+  JsonScanner scanner_;
 };
 } }  // namespace v8::internal