Change the register allocator so that it no longer tracks references...

src/codegen.cc

Index: src/codegen.cc
===================================================================
--- src/codegen.cc	(revision 2055)
+++ src/codegen.cc	(working copy)
@@ -515,8 +515,8 @@
     // frame.  Otherwise, we have to merge the existing one to the
     // start frame as part of the previous case.
     if (!has_valid_frame()) {
-      RegisterFile non_frame_registers = RegisterAllocator::Reserved();
-      SetFrame(new VirtualFrame(start_frame), &non_frame_registers);
+      RegisterFile empty;
+      SetFrame(new VirtualFrame(start_frame), &empty);
     } else {
       frame_->MergeTo(start_frame);
     }