Remove feature-gate code

src/librustc/lint/levels.rs

@@ -22,7 +22,6 @@ use session::{config::nightly_options, Session};
 use syntax::ast;
 use syntax::attr;
 use syntax::source_map::MultiSpan;
-use syntax::feature_gate;
 use syntax::symbol::Symbol;
 use util::nodemap::FxHashMap;
 
@@ -228,28 +227,14 @@ impl<'a> LintLevelsBuilder<'a> {
  }
  };
  let tool_name = if let Some(lint_tool) = word.is_scoped() {
- let gate_feature = !self.sess.features_untracked().tool_lints;
- let known_tool = attr::is_known_lint_tool(lint_tool);
- if gate_feature {
- feature_gate::emit_feature_err(
- &sess.parse_sess,
- "tool_lints",
- word.span,
- feature_gate::GateIssue::Language,
- &format!("scoped lint `{}` is experimental", word.ident),
- );
- }
- if !known_tool {
+ if !attr::is_known_lint_tool(lint_tool) {
  span_err!(
  sess,
  lint_tool.span,
  E0710,
  "an unknown tool name found in scoped lint: `{}`",
  word.ident
  );
- }
-
- if gate_feature || !known_tool {
  continue;
  }