Allow direct allocation in old pointer space.

src/assembler.h

Index: src/assembler.h
diff --git a/src/assembler.h b/src/assembler.h
index 06c3b760a60949a5cd30cec77d8e24ae93e51ee4..820c89b4545f433e62565ff58a65523b2fab2655 100644
--- a/src/assembler.h
+++ b/src/assembler.h
@@ -717,6 +717,10 @@ class ExternalReference BASE_EMBEDDED {
   // Used for fast allocation in generated code.
   static ExternalReference new_space_allocation_top_address(Isolate* isolate);
   static ExternalReference new_space_allocation_limit_address(Isolate* isolate);
+  static ExternalReference old_pointer_space_allocation_top_address(
+      Isolate* isolate);
+  static ExternalReference old_pointer_space_allocation_limit_address(
+      Isolate* isolate);
 
   static ExternalReference double_fp_operation(Token::Value operation,
                                                Isolate* isolate);