text/template: remove unnecessary lexer field

this change removes the state field from the lexer,
because it's only used by the run method and can be
replaced with a local variable

Change-Id: Ib7a90ab6e9a894716cba2c7d9ed71bf2ad1240c0
Reviewed-on: https://go-review.googlesource.com/47338Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/text/template/parse/lex.go

@@ -114,7 +114,6 @@ type lexer struct {
 	input      string    // the string being scanned
 	leftDelim  string    // start of action
 	rightDelim string    // end of action
-	state      stateFn   // the next lexing function to enter
 	pos        Pos       // current position in the input
 	start      Pos       // start position of this item
 	width      Pos       // width of last rune read from input
@@ -229,8 +228,8 @@ func lex(name, input, left, right string) *lexer {
 
 // run runs the state machine for the lexer.
 func (l *lexer) run() {
-	for l.state = lexText; l.state != nil; {
-		l.state = l.state(l)
+	for state := lexText; state != nil; {
+		state = state(l)
 	}
 	close(l.items)
 }