all: remove strings.Contains check around Replace

It doesn't change the outcome. It might have been useful at some point
to avoid Replace from doing work or allocating. However, nowadays the
func returns early without doing any work if Count returns 0.

Change-Id: Id69dc74042a6e39672b405016484db8b50f43d58
Reviewed-on: https://go-review.googlesource.com/62991
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>

src/path/filepath/path_windows.go

@@ -100,9 +100,7 @@ func splitList(path string) []string {
 
 	// Remove quotes.
 	for i, s := range list {
-		if strings.Contains(s, `"`) {
-			list[i] = strings.Replace(s, `"`, ``, -1)
-		}
+		list[i] = strings.Replace(s, `"`, ``, -1)
 	}
 
 	return list

src/text/template/exec.go

@@ -79,10 +79,7 @@ func (s *state) at(node parse.Node) {
 // doublePercent returns the string with %'s replaced by %%, if necessary,
 // so it can be used safely inside a Printf format string.
 func doublePercent(str string) string {
-	if strings.Contains(str, "%") {
-		str = strings.Replace(str, "%", "%%", -1)
-	}
-	return str
+	return strings.Replace(str, "%", "%%", -1)
 }
 
 // TODO: It would be nice if ExecError was more broken down, but