Move StateStore into the snapshot

src/atom-environment.coffee

@@ -143,6 +143,8 @@ class AtomEnvironment extends Model
     @views = new ViewRegistry(this)
     @notifications = new NotificationManager
 
+    @stateStore = new StateStore('AtomEnvironments', 1)
+
     @config = new Config({notificationManager: @notifications, @enablePersistence})
     @config.setSchema null, {type: 'object', properties: _.clone(ConfigSchema)}
 
@@ -192,7 +194,7 @@ class AtomEnvironment extends Model
 
     @windowEventHandler = new WindowEventHandler({atomEnvironment: this, @applicationDelegate})
 
-    @history = new HistoryManager({@project, @commands})
+    @history = new HistoryManager({@project, @commands, @stateStore})
     # Keep instances of HistoryManager in sync
     @disposables.add @history.onDidChangeProjects (e) =>
       @applicationDelegate.didChangeHistoryManager() unless e.reloaded
@@ -201,8 +203,6 @@ class AtomEnvironment extends Model
     {@window, @document, @blobStore, @configDirPath, onlyLoadBaseStyleSheets} = params
     {devMode, safeMode, resourcePath, clearWindowState} = @getLoadSettings()
 
-    @stateStore = new StateStore('AtomEnvironments', 1)
-
     if clearWindowState
       @getStorageFolder().clear()
       @stateStore.clear()
@@ -255,7 +255,6 @@ class AtomEnvironment extends Model
 
     @observeAutoHideMenuBar()
 
-    @history.initialize(@stateStore)
     @disposables.add @applicationDelegate.onDidChangeHistoryManager(=> @history.loadState())
 
   attachSaveStateListeners: ->

src/history-manager.js

@@ -8,7 +8,8 @@ import {Emitter, CompositeDisposable} from 'event-kit'
 //
 // The project history is used to enable the 'Reopen Project' menu.
 export class HistoryManager {
-  constructor ({project, commands}) {
+  constructor ({project, commands, stateStore}) {
+    this.stateStore = stateStore
     this.emitter = new Emitter()
     this.projects = []
     this.disposables = new CompositeDisposable()
@@ -16,10 +17,6 @@ export class HistoryManager {
     this.disposables.add(project.onDidChangePaths((projectPaths) => this.addProject(projectPaths)))
   }
 
-  initialize (stateStore) {
-    this.stateStore = stateStore
-  }
-
   destroy () {
     this.disposables.dispose()
   }

src/state-store.js

@@ -4,22 +4,31 @@ module.exports =
 class StateStore {
   constructor (databaseName, version) {
     this.connected = false
-    this.dbPromise = new Promise((resolve) => {
-      let dbOpenRequest = indexedDB.open(databaseName, version)
-      dbOpenRequest.onupgradeneeded = (event) => {
-        let db = event.target.result
-        db.createObjectStore('states')
-      }
-      dbOpenRequest.onsuccess = () => {
-        this.connected = true
-        resolve(dbOpenRequest.result)
-      }
-      dbOpenRequest.onerror = (error) => {
-        console.error('Could not connect to indexedDB', error)
-        this.connected = false
-        resolve(null)
-      }
-    })
+    this.databaseName = databaseName
+    this.version = version
+  }
+
+  get dbPromise () {
+    if (!this._dbPromise) {
+      this._dbPromise = new Promise((resolve) => {
+        const dbOpenRequest = indexedDB.open(this.databaseName, this.version)
+        dbOpenRequest.onupgradeneeded = (event) => {
+          let db = event.target.result
+          db.createObjectStore('states')
+        }
+        dbOpenRequest.onsuccess = () => {
+          this.connected = true
+          resolve(dbOpenRequest.result)
+        }
+        dbOpenRequest.onerror = (error) => {
+          console.error('Could not connect to indexedDB', error)
+          this.connected = false
+          resolve(null)
+        }
+      })
+    }
+
+    return this._dbPromise
   }
 
   isConnected () {