Revert of Add unoptimized/optimized variants of MathFloor TF code stub

src/interface-descriptors.h

Index: src/interface-descriptors.h
diff --git a/src/interface-descriptors.h b/src/interface-descriptors.h
index 7fa70f1b38c8974222feb936e2aedc16b33b8dd1..f206b55841443bd19a6ff7b37ec7334fd87e5b90 100644
--- a/src/interface-descriptors.h
+++ b/src/interface-descriptors.h
@@ -61,8 +61,7 @@
   V(MathPowInteger)                           \
   V(ContextOnly)                              \
   V(GrowArrayElements)                        \
-  V(MathRoundVariantCallFromUnoptimizedCode)  \
-  V(MathRoundVariantCallFromOptimizedCode)
+  V(MathRoundVariant)
 
 
 class CallInterfaceDescriptorData {
@@ -585,20 +584,10 @@
 };
 
 
-class MathRoundVariantCallFromOptimizedCodeDescriptor
-    : public CallInterfaceDescriptor {
- public:
-  DECLARE_DESCRIPTOR_WITH_CUSTOM_FUNCTION_TYPE(
-      MathRoundVariantCallFromOptimizedCodeDescriptor, CallInterfaceDescriptor)
-};
-
-
-class MathRoundVariantCallFromUnoptimizedCodeDescriptor
-    : public CallInterfaceDescriptor {
- public:
-  DECLARE_DESCRIPTOR_WITH_CUSTOM_FUNCTION_TYPE(
-      MathRoundVariantCallFromUnoptimizedCodeDescriptor,
-      CallInterfaceDescriptor)
+class MathRoundVariantDescriptor : public CallInterfaceDescriptor {
+ public:
+  DECLARE_DESCRIPTOR_WITH_CUSTOM_FUNCTION_TYPE(MathRoundVariantDescriptor,
+                                               CallInterfaceDescriptor)
 };