Upgrade and fix sinon.js

Converted version downloaded from sinonjs.org. Fixed version that
doesn't register itself on the global object. This forces all modules to
do a proper import.

tests/karma-test-main.js

@@ -12,7 +12,4 @@ require.config({
     baseUrl: '/base',
     deps: allTestFiles,
     callback: window.__karma__.start,
-    paths: {
-        'sinon': 'vendor/sinon',
-    },
 });

tests/test.display.js

@@ -6,7 +6,7 @@ import Display from '../core/display.js';
 import { _forceCursorURIs, browserSupportsCursorURIs } from '../core/util/browsers.js';
 
 import './assertions.js';
-import 'sinon';
+import sinon from '../vendor/sinon.js';
 import sinonChai from '../node_modules/sinon-chai/lib/sinon-chai.js';
 chai.use(sinonChai);
 

tests/test.keyboard.js

@@ -1,6 +1,8 @@
 var assert = chai.assert;
 var expect = chai.expect;
 
+import sinon from '../vendor/sinon.js';
+
 import Keyboard from '../core/input/keyboard.js';
 
 function isIE() {

tests/test.mouse.js

@@ -1,6 +1,8 @@
 var assert = chai.assert;
 var expect = chai.expect;
 
+import sinon from '../vendor/sinon.js';
+
 import Mouse from '../core/input/mouse.js';
 import * as eventUtils from '../core/util/events.js';
 

tests/test.rfb.js

@@ -7,7 +7,7 @@ import Websock from '../core/websock.js';
 
 import FakeWebSocket from './fake.websocket.js';
 import './assertions';
-import 'sinon';
+import sinon from '../vendor/sinon.js';
 import sinonChai from '../node_modules/sinon-chai/lib/sinon-chai.js';
 chai.use(sinonChai);
 

tests/test.util.js

@@ -6,7 +6,7 @@ var expect = chai.expect;
 import * as Log from '../core/util/logging.js';
 import l10nGet, { l10n } from '../core/util/localization.js';
 
-import 'sinon';
+import sinon from '../vendor/sinon.js';
 import sinonChai from '../node_modules/sinon-chai/lib/sinon-chai.js';
 chai.use(sinonChai);
 

tests/test.websock.js

@@ -6,7 +6,7 @@ import Websock from '../core/websock.js';
 import FakeWebSocket from './fake.websocket.js';
 
 import './assertions';
-import 'sinon';
+import sinon from '../vendor/sinon.js';
 import sinonChai from '../node_modules/sinon-chai/lib/sinon-chai.js';
 chai.use(sinonChai);