X87: [turbofan] Add AllocateHeapNumberStub to avoid runtime call.

src/x87/interface-descriptors-x87.cc

Index: src/x87/interface-descriptors-x87.cc
diff --git a/src/x87/interface-descriptors-x87.cc b/src/x87/interface-descriptors-x87.cc
index 764034391bcdd8bbb3aaef2593b7d57db6bf5c6a..26ce4dcb857f0fe2cbacf4eb0e9ae0722e6b0052 100644
--- a/src/x87/interface-descriptors-x87.cc
+++ b/src/x87/interface-descriptors-x87.cc
@@ -155,6 +155,15 @@ void TransitionElementsKindDescriptor::Initialize(
 }
 
 
+void AllocateHeapNumberDescriptor::Initialize(
+    CallInterfaceDescriptorData* data) {
+  // register state
+  // esi -- context
+  Register registers[] = {esi};
+  data->Initialize(arraysize(registers), registers, nullptr);
+}
+
+
 void ArrayConstructorConstantArgCountDescriptor::Initialize(
     CallInterfaceDescriptorData* data) {
   // register state