JS: Format if statements with no else on a single line

test/codegen/expect/collection/src/canonicalized_map.js

 dart_library.library('collection/src/canonicalized_map', null, /* Imports */[
   "dart/_runtime",
   'dart/core',
   'collection/src/utils',
   'dart/collection'
 ], /* Lazy imports */[
 ], function(exports, dart, core, utils, collection) {
   'use strict';
   let dartx = dart.dartx;
   const _base = Symbol('_base');
   const _canonicalize = Symbol('_canonicalize');
   const _isValidKeyFn = Symbol('_isValidKeyFn');
   const _isValidKey = Symbol('_isValidKey');
   const CanonicalizedMap$ = dart.generic(function(C, K, V) {
     class CanonicalizedMap extends core.Object {
       CanonicalizedMap(canonicalize, opts) {
         let isValidKey = opts && 'isValidKey' in opts ? opts.isValidKey : null;
         this[_base] = core.Map$(C, utils.Pair$(K, V)).new();
         this[_canonicalize] = canonicalize;
         this[_isValidKeyFn] = isValidKey;
       }
       from(other, canonicalize, opts) {
         let isValidKey = opts && 'isValidKey' in opts ? opts.isValidKey : null;
         this[_base] = core.Map$(C, utils.Pair$(K, V)).new();
         this[_canonicalize] = canonicalize;
         this[_isValidKeyFn] = isValidKey;
         this.addAll(other);
       }
       get(key) {
-        if (!dart.notNull(this[_isValidKey](key)))
-          return null;
+        if (!dart.notNull(this[_isValidKey](key))) return null;
         let pair = this[_base].get(dart.dcall(this[_canonicalize], key));
         return pair == null ? null : pair.last;
       }
       set(key, value) {
         dart.as(key, K);
         dart.as(value, V);
         this[_base].set(dart.as(dart.dcall(this[_canonicalize], key), C), new (utils.Pair$(K, V))(key, value));
         return value;
       }
       addAll(other) {
         dart.as(other, core.Map$(K, V));
         other.forEach(dart.fn((key, value) => this.set(dart.as(key, K), dart.as(value, V))));
       }
       clear() {
         this[_base].clear();
       }
       containsKey(key) {
-        if (!dart.notNull(this[_isValidKey](key)))
-          return false;
+        if (!dart.notNull(this[_isValidKey](key))) return false;
         return this[_base].containsKey(dart.dcall(this[_canonicalize], key));
       }
       containsValue(value) {
         return this[_base].values[dartx.any](dart.fn(pair => dart.equals(dart.dload(pair, 'last'), value), core.bool, [dart.dynamic]));
       }
       forEach(f) {
         dart.as(f, dart.functionType(dart.void, [K, V]));
         this[_base].forEach(dart.fn((key, pair) => f(dart.as(dart.dload(pair, 'first'), K), dart.as(dart.dload(pair, 'last'), V)), dart.void, [dart.dynamic, dart.dynamic]));
       }
       get isEmpty() {
         return this[_base].isEmpty;
       }
       get isNotEmpty() {
         return this[_base].isNotEmpty;
       }
       get keys() {
         return dart.as(this[_base].values[dartx.map](dart.fn(pair => dart.dload(pair, 'first'))), core.Iterable$(K));
       }
       get length() {
         return this[_base].length;
       }
       putIfAbsent(key, ifAbsent) {
         dart.as(key, K);
         dart.as(ifAbsent, dart.functionType(V, []));
         return this[_base].putIfAbsent(dart.as(dart.dcall(this[_canonicalize], key), C), dart.fn(() => new (utils.Pair$(K, V))(key, ifAbsent()), utils.Pair$(K, V), [])).last;
       }
       remove(key) {
-        if (!dart.notNull(this[_isValidKey](key)))
-          return null;
+        if (!dart.notNull(this[_isValidKey](key))) return null;
         let pair = this[_base].remove(dart.dcall(this[_canonicalize], key));
         return pair == null ? null : pair.last;
       }
       get values() {
         return dart.as(this[_base].values[dartx.map](dart.fn(pair => dart.dload(pair, 'last'))), core.Iterable$(V));
       }
       toString() {
         return collection.Maps.mapToString(this);
       }
       [_isValidKey](key) {
@@ skipping 20 matching lines @@
         [_isValidKey]: [core.bool, [core.Object]]
       })
     });
     return CanonicalizedMap;
   });
   let CanonicalizedMap = CanonicalizedMap$();
   // Exports:
   exports.CanonicalizedMap$ = CanonicalizedMap$;
   exports.CanonicalizedMap = CanonicalizedMap;
 });