Fix warnings of compiler_lint_functions

Author: flip1995

clippy_lints/src/double_parens.rs

@@ -1,6 +1,7 @@
 use crate::syntax::ast::*;
-use crate::rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintContext, LintPass};
+use crate::rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintPass};
 use crate::rustc::{declare_tool_lint, lint_array};
+use crate::utils::span_lint;
 
 /// **What it does:** Checks for unnecessary double parentheses.
 ///
@@ -35,20 +36,20 @@ impl EarlyLintPass for DoubleParens {
         match expr.node {
             ExprKind::Paren(ref in_paren) => match in_paren.node {
                 ExprKind::Paren(_) | ExprKind::Tup(_) => {
-                    cx.span_lint(DOUBLE_PARENS, expr.span, "Consider removing unnecessary double parentheses");
+                    span_lint(cx, DOUBLE_PARENS, expr.span, "Consider removing unnecessary double parentheses");
                 },
                 _ => {},
             },
             ExprKind::Call(_, ref params) => if params.len() == 1 {
                 let param = &params[0];
                 if let ExprKind::Paren(_) = param.node {
-                    cx.span_lint(DOUBLE_PARENS, param.span, "Consider removing unnecessary double parentheses");
+                    span_lint(cx, DOUBLE_PARENS, param.span, "Consider removing unnecessary double parentheses");
                 }
             },
             ExprKind::MethodCall(_, ref params) => if params.len() == 2 {
                 let param = &params[1];
                 if let ExprKind::Paren(_) = param.node {
-                    cx.span_lint(DOUBLE_PARENS, param.span, "Consider removing unnecessary double parentheses");
+                    span_lint(cx, DOUBLE_PARENS, param.span, "Consider removing unnecessary double parentheses");
                 }
             },
             _ => {},