go/format: quote bytes in comments for readability

Change-Id: I8e90012b3498c51aaeb2f70182debab52549afb4
Reviewed-on: https://go-review.googlesource.com/40930Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/go/format/internal.go

@@ -37,14 +37,14 @@ func parse(fset *token.FileSet, filename string, src []byte, fragmentOk bool) (
 
 	// If this is a declaration list, make it a source file
 	// by inserting a package clause.
-	// Insert using a ;, not a newline, so that the line numbers
+	// Insert using a ';', not a newline, so that the line numbers
 	// in psrc match the ones in src.
 	psrc := append([]byte("package p;"), src...)
 	file, err = parser.ParseFile(fset, filename, psrc, parserMode)
 	if err == nil {
 		sourceAdj = func(src []byte, indent int) []byte {
 			// Remove the package clause.
-			// Gofmt has turned the ; into a \n.
+			// Gofmt has turned the ';' into a '\n'.
 			src = src[indent+len("package p\n"):]
 			return bytes.TrimSpace(src)
 		}
@@ -60,7 +60,7 @@ func parse(fset *token.FileSet, filename string, src []byte, fragmentOk bool) (
 	// If this is a statement list, make it a source file
 	// by inserting a package clause and turning the list
 	// into a function body. This handles expressions too.
-	// Insert using a ;, not a newline, so that the line numbers
+	// Insert using a ';', not a newline, so that the line numbers
 	// in fsrc match the ones in src. Add an extra '\n' before the '}'
 	// to make sure comments are flushed before the '}'.
 	fsrc := append(append([]byte("package p; func _() {"), src...), '\n', '\n', '}')
@@ -72,7 +72,7 @@ func parse(fset *token.FileSet, filename string, src []byte, fragmentOk bool) (
 				indent = 0
 			}
 			// Remove the wrapping.
-			// Gofmt has turned the ; into a \n\n.
+			// Gofmt has turned the ';' into a '\n'.
 			// There will be two non-blank lines with indent, hence 2*indent.
 			src = src[2*indent+len("package p\n\nfunc _() {"):]
 			// Remove only the "}\n" suffix: remaining whitespaces will be trimmed anyway