Revert of Add web compat workarounds for ES2015 RegExp semantics

src/runtime/runtime-internal.cc

Index: src/runtime/runtime-internal.cc
diff --git a/src/runtime/runtime-internal.cc b/src/runtime/runtime-internal.cc
index ee664645d4b9e368676cfe9be2fd69bffcbb69b8..4df0c1b45a17b6c6e836365cd3d116e5a60041ec 100644
--- a/src/runtime/runtime-internal.cc
+++ b/src/runtime/runtime-internal.cc
@@ -460,14 +460,5 @@
   return *result;
 }
 
-
-RUNTIME_FUNCTION(Runtime_IncrementUseCounter) {
-  HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  CONVERT_SMI_ARG_CHECKED(counter, 0);
-  isolate->CountUsage(static_cast<v8::Isolate::UseCounterFeature>(counter));
-  return isolate->heap()->undefined_value();
-}
-
 }  // namespace internal
 }  // namespace v8