Tidy build constraints in mathutil (pingcap#14257)

- Rename *_js.go to *_wasm.go to satisfy both wasm/js and wasm/wasi
- Use +build instruction instead of *_GOOS pattern to reduce file

Signed-off-by: lucklove <[email protected]>

Author: lucklove

executor/explain.go

@@ -16,10 +16,10 @@ package executor
 import (
 	"context"
 
-	"github.com/cznic/mathutil"
 	"github.com/pingcap/errors"
 	"github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/util/chunk"
+	"github.com/pingcap/tidb/util/mathutil"
 )
 
 // ExplainExec represents an explain executor.

go.mod

@@ -34,7 +34,7 @@ require (
 	github.com/pingcap/errors v0.11.5-0.20190809092503-95897b64e011
 	github.com/pingcap/failpoint v0.0.0-20191029060244-12f4ac2fd11d
 	github.com/pingcap/fn v0.0.0-20191016082858-07623b84a47d
-	github.com/pingcap/goleveldb v0.0.0-20171020122428-b9ff6c35079e
+	github.com/pingcap/goleveldb v0.0.0-20191226122134-f82aafb29989
 	github.com/pingcap/kvproto v0.0.0-20191217072959-393e6c0fd4b7
 	github.com/pingcap/log v0.0.0-20191012051959-b742a5d432e9
 	github.com/pingcap/parser v0.0.0-20191223023445-b93660cf3e4e

go.sum

@@ -195,6 +195,8 @@ github.com/pingcap/fn v0.0.0-20191016082858-07623b84a47d h1:rCmRK0lCRrHMUbS99BKF
 github.com/pingcap/fn v0.0.0-20191016082858-07623b84a47d/go.mod h1:fMRU1BA1y+r89AxUoaAar4JjrhUkVDt0o0Np6V8XbDQ=
 github.com/pingcap/goleveldb v0.0.0-20171020122428-b9ff6c35079e h1:P73/4dPCL96rGrobssy1nVy2VaVpNCuLpCbr+FEaTA8=
 github.com/pingcap/goleveldb v0.0.0-20171020122428-b9ff6c35079e/go.mod h1:O17XtbryoCJhkKGbT62+L2OlrniwqiGLSqrmdHCMzZw=
+github.com/pingcap/goleveldb v0.0.0-20191226122134-f82aafb29989 h1:surzm05a8C9dN8dIUmo4Be2+pMRb6f55i+UIYrluu2E=
+github.com/pingcap/goleveldb v0.0.0-20191226122134-f82aafb29989/go.mod h1:O17XtbryoCJhkKGbT62+L2OlrniwqiGLSqrmdHCMzZw=
 github.com/pingcap/kvproto v0.0.0-20191211054548-3c6b38ea5107 h1:IXAs9fKFQZJVHf9cXWfUh8Nq8zPO9ihgPgNuU1j7bIo=
 github.com/pingcap/kvproto v0.0.0-20191211054548-3c6b38ea5107/go.mod h1:WWLmULLO7l8IOcQG+t+ItJ3fEcrL5FxF0Wu+HrMy26w=
 github.com/pingcap/kvproto v0.0.0-20191213111810-93cb7c623c8b/go.mod h1:WWLmULLO7l8IOcQG+t+ItJ3fEcrL5FxF0Wu+HrMy26w=

util/mathutil/mathutil_darwin.go util/mathutil/mathutil.go

@@ -10,6 +10,8 @@
 // distributed under the License is distributed on an "AS IS" BASIS,
 // See the License for the specific language governing permissions and
 // limitations under the License.
+//
+// +build darwin linux windows
 
 package mathutil