Fix buttonless update

package-lock.json

@@ -1191,8 +1191,7 @@
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/console-control-strings/-/console-control-strings-1.1.0.tgz",
       "integrity": "sha1-PXz0Rk22RG6mRL9LOVB/mFEAjo4=",
-      "dev": true,
-      "optional": true
+      "dev": true
     },
     "constants-browserify": {
       "version": "1.0.0",
@@ -3365,7 +3364,6 @@
       "resolved": "https://registry.npmjs.org/minipass/-/minipass-2.9.0.tgz",
       "integrity": "sha512-wxfUjg9WebH+CUDX/CdbRlh5SmfZiy/hpkxaRI16Y9W56Pa75sWgd/rvFilSgrauD9NyFymP/+JFV3KwzIsJeg==",
       "dev": true,
-      "optional": true,
       "requires": {
         "safe-buffer": "^5.1.2",
         "yallist": "^3.0.0"
@@ -3610,8 +3608,7 @@
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/npm-normalize-package-bin/-/npm-normalize-package-bin-1.0.1.tgz",
       "integrity": "sha512-EPfafl6JL5/rU+ot6P3gRSCpPDW5VmIzX959Ob1+ySFUuuYHWHekXpwdUZcKP5C+DS4GEtdJluwBjnsNDl+fSA==",
-      "dev": true,
-      "optional": true
+      "dev": true
     },
     "npm-packlist": {
       "version": "1.4.8",
@@ -5571,8 +5568,7 @@
       "version": "3.1.1",
       "resolved": "https://registry.npmjs.org/yallist/-/yallist-3.1.1.tgz",
       "integrity": "sha512-a4UGQaWPH59mOXUYnAG2ewncQS4i4F43Tv3JoAM+s2VDAmS9NsK8GpDMLrCHPksFT7h3K6TOoUNn2pb7RoXx4g==",
-      "dev": true,
-      "optional": true
+      "dev": true
     },
     "yargs": {
       "version": "7.1.0",

src/secure-dfu.ts

@@ -510,7 +510,7 @@ export class SecureDfu extends EventDispatcher {
                 })
                 .then(() => {
                     this.log("sent DFU mode");
-                    complete();
+                    complete.call(this);
                 });
             });
         });