@uppy/utils: remove EventManager circular reference

[Murderlon]

Users may not update all their Uppy packages at once, moving the EventManager class to core ended up breaking some users. Moving the class was necessary for the TS transition, but we could live with some duplicated code until we release 4.0.0.
This PR re-introduce the EventManager.js file as it was before the TS transition, it’s only there for backward compatibility. Uppy plugins should keep referencing the one in @uppy/core.

[github-actions]

Diff output files

diff --git a/packages/@uppy/utils/lib/EventManager.js b/packages/@uppy/utils/lib/EventManager.js
index fd19927..05ee7f4 100644
--- a/packages/@uppy/utils/lib/EventManager.js
+++ b/packages/@uppy/utils/lib/EventManager.js
@@ -1 +1,85 @@
-export { default } from "@uppy/core/lib/EventManager.js";
+function _classPrivateFieldLooseBase(receiver, privateKey) {
+  if (!Object.prototype.hasOwnProperty.call(receiver, privateKey)) {
+    throw new TypeError("attempted to use private field on non-instance");
+  }
+  return receiver;
+}
+var id = 0;
+function _classPrivateFieldLooseKey(name) {
+  return "__private_" + id++ + "_" + name;
+}
+var _uppy = _classPrivateFieldLooseKey("uppy");
+var _events = _classPrivateFieldLooseKey("events");
+export default class EventManager {
+  constructor(uppy) {
+    Object.defineProperty(this, _uppy, {
+      writable: true,
+      value: void 0,
+    });
+    Object.defineProperty(this, _events, {
+      writable: true,
+      value: [],
+    });
+    _classPrivateFieldLooseBase(this, _uppy)[_uppy] = uppy;
+  }
+  on(event, fn) {
+    _classPrivateFieldLooseBase(this, _events)[_events].push([event, fn]);
+    return _classPrivateFieldLooseBase(this, _uppy)[_uppy].on(event, fn);
+  }
+  remove() {
+    for (const [event, fn] of _classPrivateFieldLooseBase(this, _events)[_events].splice(0)) {
+      _classPrivateFieldLooseBase(this, _uppy)[_uppy].off(event, fn);
+    }
+  }
+  onFilePause(fileID, cb) {
+    this.on("upload-pause", (targetFileID, isPaused) => {
+      if (fileID === targetFileID) {
+        cb(isPaused);
+      }
+    });
+  }
+  onFileRemove(fileID, cb) {
+    this.on("file-removed", file => {
+      if (fileID === file.id) cb(file.id);
+    });
+  }
+  onPause(fileID, cb) {
+    this.on("upload-pause", (targetFileID, isPaused) => {
+      if (fileID === targetFileID) {
+        cb(isPaused);
+      }
+    });
+  }
+  onRetry(fileID, cb) {
+    this.on("upload-retry", targetFileID => {
+      if (fileID === targetFileID) {
+        cb();
+      }
+    });
+  }
+  onRetryAll(fileID, cb) {
+    this.on("retry-all", () => {
+      if (!_classPrivateFieldLooseBase(this, _uppy)[_uppy].getFile(fileID)) return;
+      cb();
+    });
+  }
+  onPauseAll(fileID, cb) {
+    this.on("pause-all", () => {
+      if (!_classPrivateFieldLooseBase(this, _uppy)[_uppy].getFile(fileID)) return;
+      cb();
+    });
+  }
+  onCancelAll(fileID, eventHandler) {
+    var _this = this;
+    this.on("cancel-all", function() {
+      if (!_classPrivateFieldLooseBase(_this, _uppy)[_uppy].getFile(fileID)) return;
+      eventHandler(...arguments);
+    });
+  }
+  onResumeAll(fileID, cb) {
+    this.on("resume-all", () => {
+      if (!_classPrivateFieldLooseBase(this, _uppy)[_uppy].getFile(fileID)) return;
+      cb();
+    });
+  }
+}