Fix compilation failure on ia32 and x64.

TBR=ager

BUG=
TEST=

Review URL: http://codereview.chromium.org/6359001

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6331 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/frames.cc

@@ -555,7 +555,7 @@ void OptimizedFrame::Iterate(ObjectVisitor* v) const {
   }
 
   if (safepoint_entry.has_doubles()) {
-    parameters_base += DwVfpRegister::kNumAllocatableRegisters *
+    parameters_base += DoubleRegister::kNumAllocatableRegisters *
         kDoubleSize / kPointerSize;
   }