[TypeChecker] NFC: Extend scale and move test-case for rdar://30606089 to "fast"

Resolves: SR-6520

Author: xedin

validation-test/Sema/type_checker_perf/fast/rdar30606089.swift.gyb

@@ -0,0 +1,11 @@
+// RUN: %scale-test --begin 1 --end 20 --step 1 --select NumLeafScopes %s --polynomial-threshold 1.7
+// REQUIRES: asserts,no_asan
+
+let derivative = { (t: Double) -> (Double) in
+  return -2.0 / (
+  (1.0 + t)
+%for i in range(1, N):
+  * (1.0 + t)
+%end
+  )
+}