Remove register counts from VirtualFrame, use register indices instead.

src/jump-target.cc

Index: src/jump-target.cc
===================================================================
--- src/jump-target.cc	(revision 1604)
+++ src/jump-target.cc	(working copy)
@@ -272,14 +272,13 @@
 
   // Set the copied flags in the frame to be exact.  This assumes that
   // the backing store of copies is always lower in the frame.
-  // Set the register counts and indices.
+  // Set the register locations to their index in the frame.
   for (int i = 0; i < length; i++) {
     FrameElement current = entry_frame_->elements_[i];
     entry_frame_->elements_[i].clear_copied();
     if (current.is_copy()) {
       entry_frame_->elements_[current.index()].set_copied();
     } else if (current.is_register()) {
-      entry_frame_->frame_registers_.Use(current.reg());
       entry_frame_->register_locations_[current.reg().code()] = i;
     }
   }