test: add copyright notice to typecheck.go

Also gofmt.

Change-Id: I36ac990965250867574f8e2318b65b87a0beda04
Reviewed-on: https://go-review.googlesource.com/c/go/+/228697
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/test/typecheck.go b/test/typecheck.go
index 6f12042..4c55d2e 100644
--- a/test/typecheck.go
+++ b/test/typecheck.go
@@ -1,5 +1,9 @@
 // errorcheck
 
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
 // Verify that the Go compiler will not
 // die after running into an undefined
 // type in the argument list for a
@@ -8,11 +12,11 @@
 
 package main
 
-func mine(int b) int {	// ERROR "undefined.*b"
-	return b + 2	// ERROR "undefined.*b"
+func mine(int b) int { // ERROR "undefined.*b"
+	return b + 2 // ERROR "undefined.*b"
 }
 
 func main() {
-	mine()		// GCCGO_ERROR "not enough arguments"
-	c = mine()	// ERROR "undefined.*c|not enough arguments"
+	mine()     // GCCGO_ERROR "not enough arguments"
+	c = mine() // ERROR "undefined.*c|not enough arguments"
 }