add and use init in executioncontext

src/app.js

@@ -109,6 +109,7 @@ class App {
     self._api = {}
     var fileStorage = new Storage('sol:')
     self._api.config = new Config(fileStorage)
+    executionContext.init(self._api.config)
     self._api.filesProviders = {}
     self._api.filesProviders['browser'] = new Browserfiles(fileStorage)
     self._api.filesProviders['localhost'] = new SharedFolder(new Remixd())

src/execution-context.js

@@ -82,7 +82,16 @@ var mainNetGenesisHash = '0xd4e56740f876aef8c010b86a40d5f56745a118d0906a34e69aec
 function ExecutionContext () {
   var self = this
   this.event = new EventManager()
-  var executionContext = 'vm'
+
+  var executionContext = null
+
+  this.init = function (config) {
+    if (config.get('settings/always-use-vm')) {
+      executionContext = 'vm'
+    } else {
+      executionContext = injectedProvider ? 'injected' : 'vm'
+    }
+  }
 
   this.getProvider = function () {
     return executionContext