Reverting 3174. Aka reapplying 3150, 3151 and 3159. Aka api accessor

src/assembler.h

Index: src/assembler.h
diff --git a/src/assembler.h b/src/assembler.h
index 21a66dd501aaa90e5eced81be07a19828945c4a6..311dadd53c3cc4769efe9c7ec977eeed479a94ba 100644
--- a/src/assembler.h
+++ b/src/assembler.h
@@ -373,6 +373,8 @@ class ExternalReference BASE_EMBEDDED {
  public:
   explicit ExternalReference(Builtins::CFunctionId id);
 
+  explicit ExternalReference(ApiFunction* ptr);
+
   explicit ExternalReference(Builtins::Name name);
 
   explicit ExternalReference(Runtime::FunctionId id);
@@ -422,6 +424,12 @@ class ExternalReference BASE_EMBEDDED {
   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