Implement IconServices singleton with lazy getter

This avoids constructing this object at eval-time, which interferes with
building Atom's v8 snapshot when this package is bundled.

/cc @Alhadis

Author: Nathan Sobo

lib/fuzzy-finder-view.js

@@ -8,7 +8,7 @@ import path from 'path'
 import SelectListView from 'atom-select-list'
 
 import {repositoryForPath} from './helpers'
-import IconServices from './icon-services'
+import getIconServices from './get-icon-services'
 
 export default class FuzzyFinderView {
   constructor () {
@@ -96,7 +96,7 @@ export default class FuzzyFinderView {
         this.secondaryLine.appendChild(highlight(projectRelativePath, matches, 0))
         li.appendChild(this.secondaryLine)
 
-        IconServices.updateIcon(this)
+        getIconServices().updateIcon(this)
         return li
       }
     })

lib/icon-services.js lib/get-icon-services.jslib/icon-services.js renamed to lib/get-icon-services.js

@@ -1,6 +1,12 @@
 const DefaultFileIcons = require('./default-file-icons')
 const {Emitter, CompositeDisposable} = require('atom')
 
+let iconServices
+module.exports = function () {
+  if (!iconServices) iconServices = new IconServices()
+  return iconServices
+}
+
 class IconServices {
   constructor () {
     this.emitter = new Emitter()
@@ -55,5 +61,3 @@ class IconServices {
     }
   }
 }
-
-module.exports = new IconServices()

lib/main.js

@@ -1,5 +1,5 @@
 const {Disposable} = require('atom')
-const IconServices = require('./icon-services')
+const getIconServices = require('./get-icon-services')
 
 module.exports = {
   activate (state) {
@@ -49,13 +49,13 @@ module.exports = {
   },
 
   consumeElementIcons (service) {
-    IconServices.setElementIcons(service)
-    return new Disposable(() => IconServices.resetElementIcons())
+    getIconServices().setElementIcons(service)
+    return new Disposable(() => getIconServices().resetElementIcons())
   },
 
   consumeFileIcons (service) {
-    IconServices.setFileIcons(service)
-    return new Disposable(() => IconServices.resetFileIcons())
+    getIconServices().setFileIcons(service)
+    return new Disposable(() => getIconServices().resetFileIcons())
   },
 
   serialize () {