fix(rules): fixes eslint-6.x compatibility

.eslintrc.json

@@ -15,6 +15,7 @@
             "error",
             "unix"
         ],
+        "no-prototype-builtins": "off",
         "quotes": [
             "error",
             "single"

lib/rules/array-callback-return.js

@@ -5,16 +5,9 @@
  * @author Alexander Afanasyev (based on Toru Nagashima's work)
  */
 
-var astUtils
-
-try {
-  astUtils = require('eslint/lib/util/ast-utils')
-} catch (err) {
-  astUtils = require('eslint/lib/ast-utils')
-}
-
 var isElementArrayFinder = require('../is-element-array-finder')
 
+var ANY_FUNCTION_PATTERN = /^(?:Function(?:Declaration|Expression)|ArrowFunctionExpression)$/
 var TARGET_NODE_TYPE = /^(?:Arrow)?FunctionExpression$/
 var TARGET_METHODS = /^(?:filter|map|reduce)$/
 
@@ -45,6 +38,29 @@ function getLocation (node, sourceCode) {
   return node.id || node
 }
 
+/**
+ * Finds a function node from ancestors of a node.
+ * @param {ASTNode} node - A start node to find.
+ * @returns {Node|null} A found function node.
+ */
+function getUpperFunction (node) {
+  for (var currentNode = node; currentNode; currentNode = currentNode.parent) {
+    if (ANY_FUNCTION_PATTERN.test(currentNode.type)) {
+      return currentNode
+    }
+  }
+  return null
+}
+
+/**
+ * Checks whether or not a node is callee.
+ * @param {ASTNode} node - A node to check.
+ * @returns {boolean} Whether or not the node is callee.
+ */
+function isCallee (node) {
+  return node.parent.type === 'CallExpression' && node.parent.callee === node
+}
+
 /**
  * Checks a given node is a MemberExpression node which has the specified name's
  * property.
@@ -80,9 +96,9 @@ function isCallbackOfArrayMethod (node) {
         break
 
       case 'ReturnStatement':
-        var func = astUtils.getUpperFunction(parent)
+        var func = getUpperFunction(parent)
 
-        if (func === null || !astUtils.isCallee(func)) {
+        if (func === null || !isCallee(func)) {
           return false
         }
         node = func.parent