Implemented specialized stubs for API getters. This includes a number...

src/assembler.h

Index: src/assembler.h
===================================================================
--- src/assembler.h	(revision 3149)
+++ src/assembler.h	(working copy)
@@ -373,6 +373,8 @@
  public:
   explicit ExternalReference(Builtins::CFunctionId id);
 
+  explicit ExternalReference(ApiFunction* ptr);
+
   explicit ExternalReference(Builtins::Name name);
 
   explicit ExternalReference(Runtime::FunctionId id);
@@ -422,6 +424,12 @@
   static ExternalReference double_fp_operation(Token::Value operation);
   static ExternalReference compare_doubles();
 
+  static ExternalReference handle_scope_extensions_address();
+  static ExternalReference handle_scope_next_address();
+  static ExternalReference handle_scope_limit_address();
+
+  static ExternalReference scheduled_exception_address();
+
   Address address() const {return reinterpret_cast<Address>(address_);}
 
 #ifdef ENABLE_DEBUGGER_SUPPORT