Merge old data and pointer space.

src/assembler.h

Index: src/assembler.h
diff --git a/src/assembler.h b/src/assembler.h
index 983ca32612794c35e1280bd4cc74e0e9da2cac3f..07859b3f8bec81525952ea1d86b1a106aa2959f5 100644
--- a/src/assembler.h
+++ b/src/assembler.h
@@ -936,14 +936,8 @@ 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 old_data_space_allocation_top_address(
-      Isolate* isolate);
-  static ExternalReference old_data_space_allocation_limit_address(
-      Isolate* isolate);
+  static ExternalReference old_space_allocation_top_address(Isolate* isolate);
+  static ExternalReference old_space_allocation_limit_address(Isolate* isolate);
 
   static ExternalReference mod_two_doubles_operation(Isolate* isolate);
   static ExternalReference power_double_double_function(Isolate* isolate);