build: out-source eventOn in dedicated package

Author: gruhn

package.json

@@ -80,6 +80,7 @@
   },
   "dependencies": {
     "babel-runtime": "^6.26.0",
+    "callforth": "^0.3.0",
     "jsqr": "^1.2.0",
     "webrtc-adapter": "^6.2.1"
   },

src/misc/camera.js

@@ -1,7 +1,7 @@
 import adapterFactory from "webrtc-adapter/src/js/adapter_factory.js";
 import { StreamApiNotSupportedError } from "./errors.js";
 import { imageDataFromVideo } from "./image-data.js";
-import { eventOn } from "./promisify.js";
+import { eventOn } from "callforth";
 
 class Camera {
   constructor(videoEl, stream) {

src/misc/image-data.js

@@ -1,5 +1,5 @@
 import { DropImageFetchError, DropImageDecodeError } from "./errors.js";
-import { eventOn } from "./promisify.js";
+import { eventOn } from "callforth";
 
 const canvas = document.createElement("canvas");
 const canvasCtx = canvas.getContext("2d");

src/misc/promisify.js

@@ -1,4 +1,4 @@
-import { eventOn } from "./promisify.js";
+import { eventOn } from "callforth";
 import Worker from "./worker.js";
 
 export async function scan(imageData) {

src/misc/scanner.js

@@ -1392,6 +1392,11 @@ caller-path@^2.0.0:
   dependencies:
     caller-callsite "^2.0.0"
 
+callforth@^0.3.0:
+  version "0.3.0"
+  resolved "https://registry.yarnpkg.com/callforth/-/callforth-0.3.0.tgz#3ff358c8bc67f72afae1a11dd90835e8139d9fe6"
+  integrity sha512-f2WARW6XXXZBEUshqoBhcWq9UxCYSCFJ0C3/hpdoXQTnhos3HQV1z7ATJVDmTp4LgjZ0leW2mBhp6T797PhwDQ==
+
 callsites@^0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/callsites/-/callsites-0.2.0.tgz#afab96262910a7f33c19a5775825c69f34e350ca"