godoc: don't double HTML-escape search result snippets

Fixes #1412.

R=rsc, r
CC=golang-dev
https://golang.org/cl/3994041

src/cmd/godoc/format.go

@@ -93,7 +93,7 @@ func FormatSelections(w io.Writer, text []byte, lw LinkWriter, links Selection,
 	segment := func(end int) {
 		if lastOffs < end { // ignore empty segments
 			if last.end != lastOffs || last.bitset != bitset {
-				// the last segment is not adjacent or
+				// the last segment is not adjacent to or
 				// differs from the new one
 				flush()
 				// start a new segment

src/cmd/godoc/snippet.go

@@ -26,7 +26,7 @@ type Snippet struct {
 func newSnippet(fset *token.FileSet, decl ast.Decl, id *ast.Ident) *Snippet {
 	// TODO instead of pretty-printing the node, should use the original source instead
 	var buf bytes.Buffer
-	writeNode(&buf, fset, decl, true)
+	writeNode(&buf, fset, decl, false)
 	return &Snippet{fset.Position(id.Pos()).Line, FormatText(buf.Bytes(), -1, true, id.Name, nil)}
 }