Use a different map to distinguish eval contexts

src/x64/interface-descriptors-x64.cc

Index: src/x64/interface-descriptors-x64.cc
diff --git a/src/x64/interface-descriptors-x64.cc b/src/x64/interface-descriptors-x64.cc
index 24fc92852a9054f404b6c6d332b6a01d0b1c6087..f1cc52325e7832b45977eef2c854de6c8381aa10 100644
--- a/src/x64/interface-descriptors-x64.cc
+++ b/src/x64/interface-descriptors-x64.cc
@@ -25,6 +25,9 @@ const Register FastNewFunctionContextDescriptor::FunctionRegister() {
 }
 const Register FastNewFunctionContextDescriptor::SlotsRegister() { return rax; }
 
+const Register FastNewEvalContextDescriptor::FunctionRegister() { return rdi; }
+const Register FastNewEvalContextDescriptor::SlotsRegister() { return rax; }
+
 const Register LoadDescriptor::ReceiverRegister() { return rdx; }
 const Register LoadDescriptor::NameRegister() { return rcx; }
 const Register LoadDescriptor::SlotRegister() { return rax; }