gofmt: simplify flags

-tabs replaces -tabindent
-spaces has been removed

R=golang-dev, adg, rsc
CC=golang-dev
https://golang.org/cl/5487066

src/cmd/gofmt/doc.go

@@ -36,10 +36,8 @@ The flags are:
 Formatting control flags:
 	-comments=true
 		Print comments; if false, all comments are elided from the output.
-	-spaces
-		Align with spaces instead of tabs.
-	-tabindent
-		Indent with tabs independent of -spaces.
+	-tabs=true
+		Indent with tabs; if false, spaces are used instead.
 	-tabwidth=8
 		Tab width in spaces.
 

src/cmd/gofmt/gofmt.go

@@ -34,8 +34,7 @@ var (
 	// layout control
 	comments  = flag.Bool("comments", true, "print comments")
 	tabWidth  = flag.Int("tabwidth", 8, "tab width")
-	tabIndent = flag.Bool("tabindent", true, "indent with tabs independent of -spaces")
-	useSpaces = flag.Bool("spaces", true, "align with spaces instead of tabs")
+	tabIndent = flag.Bool("tabs", true, "indent with tabs")
 
 	// debugging
 	cpuprofile = flag.String("cpuprofile", "", "write cpu profile to this file")
@@ -71,13 +70,10 @@ func initParserMode() {
 }
 
 func initPrinterMode() {
-	printerMode = uint(0)
+	printerMode = printer.UseSpaces
 	if *tabIndent {
 		printerMode |= printer.TabIndent
 	}
-	if *useSpaces {
-		printerMode |= printer.UseSpaces
-	}
 }
 
 func isGoFile(f os.FileInfo) bool {