math: use constant rather than variable for exported test threshold

This is a minor follow-up on https://golang.org/cl/153059.

TBR=iant

Updates #6794.

Change-Id: I03657dafc572959d46a03f86bbeb280825bc969d
Reviewed-on: https://go-review.googlesource.com/c/153845
Reviewed-by: Robert Griesemer <gri@golang.org>

diff --git a/src/math/export_test.go b/src/math/export_test.go
index 5f15bdb025d2dcfee590004628c951e1ba573b66..53d9205b9d1693d745e12695cb3d05fe576aef32 100644 (file)
--- a/src/math/export_test.go
+++ b/src/math/export_test.go
@@ -9,5 +9,6 @@ var ExpGo = exp
 var Exp2Go = exp2
 var HypotGo = hypot
 var SqrtGo = sqrt
-var ReduceThreshold = reduceThreshold
 var TrigReduce = trigReduce
+
+const ReduceThreshold = reduceThreshold