os: return from TestRemoveAllWithMoreErrorThanReqSize when RemoveAll succeeds on Windows

Also remove unused test hook.

Updates #35117

Change-Id: I6f05ba234fb09e4b44e77c1539c02d1aed49910a
Reviewed-on: https://go-review.googlesource.com/c/go/+/204060Reviewed-by: Bryan C. Mills <bcmills@google.com>

src/os/path.go

@@ -58,9 +58,6 @@ func MkdirAll(path string, perm FileMode) error {
 	return nil
 }
 
-// removeAllTestHook is a hook for testing.
-var removeAllTestHook = func(err error) error { return err }
-
 // RemoveAll removes path and any children it contains.
 // It removes everything it can but returns the first error
 // it encounters. If the path does not exist, RemoveAll

src/os/removeall_test.go

@@ -449,6 +449,11 @@ func TestRemoveAllWithMoreErrorThanReqSize(t *testing.T) {
 		return
 	}
 	if err == nil {
+		if runtime.GOOS == "windows" {
+			// Marking a directory as read-only in Windows does not prevent the RemoveAll
+			// from creating or removing files within it.
+			return
+		}
 		t.Fatal("RemoveAll(<read-only directory>) = nil; want error")
 	}
 
@@ -458,13 +463,6 @@ func TestRemoveAllWithMoreErrorThanReqSize(t *testing.T) {
 	}
 	defer dir.Close()
 
-	if runtime.GOOS == "windows" {
-		// Marking a directory in Windows does not prevent the os package from
-		// creating or removing files within it.
-		// (See https://golang.org/issue/35042.)
-		return
-	}
-
 	names, _ := dir.Readdirnames(1025)
 	if len(names) < 1025 {
 		t.Fatalf("RemoveAll(<read-only directory>) unexpectedly removed %d read-only files from that directory", 1025-len(names))