[builtins] Sanitize the machinery around Construct calls.

src/interface-descriptors.h

Index: src/interface-descriptors.h
diff --git a/src/interface-descriptors.h b/src/interface-descriptors.h
index 2c5ac4b052d8fb17702b099515c762380e072fb5..e6fa4723432847d770644ebd71ea5253e303c7b8 100644
--- a/src/interface-descriptors.h
+++ b/src/interface-descriptors.h
@@ -39,6 +39,7 @@ class PlatformInterfaceDescriptor;
   V(CallFunctionWithFeedbackAndVector)        \
   V(CallConstruct)                            \
   V(CallTrampoline)                           \
+  V(ConstructTrampoline)                      \
   V(RegExpConstructResult)                    \
   V(TransitionElementsKind)                   \
   V(AllocateHeapNumber)                       \
@@ -458,6 +459,13 @@ class CallTrampolineDescriptor : public CallInterfaceDescriptor {
 };
 
 
+class ConstructTrampolineDescriptor : public CallInterfaceDescriptor {
+ public:
+  DECLARE_DESCRIPTOR_WITH_CUSTOM_FUNCTION_TYPE(ConstructTrampolineDescriptor,
+                                               CallInterfaceDescriptor)
+};
+
+
 class CallFunctionDescriptor : public CallInterfaceDescriptor {
  public:
   DECLARE_DESCRIPTOR(CallFunctionDescriptor, CallInterfaceDescriptor)