fix(zone.js): classes that extend Error should retain cause property (angular#61599)

ZoneAwareError previously did not copy the cause property over to the
`this` object when an error extends the native error class.

PR Close angular#61599

Author: atscott

packages/zone.js/lib/common/error-rewrite.ts

@@ -143,7 +143,7 @@ export function patchError(Zone: ZoneType): void {
         // We got called with a `new` operator AND we are subclass of ZoneAwareError
         // in that case we have to copy all of our properties to `this`.
         Object.keys(error)
-          .concat('stack', 'message')
+          .concat('stack', 'message', 'cause')
           .forEach((key) => {
             const value = (error as any)[key];
             if (value !== undefined) {

packages/zone.js/test/common/Error.spec.ts

@@ -180,6 +180,21 @@ describe('ZoneAwareError', () => {
     expect(spy).toHaveBeenCalledWith('test');
   });
 
+  it('should copy cause on error that extends native', () => {
+    class WrappedError extends Error {
+      constructor(error: unknown) {
+        super(
+          'wrapped',
+          // @ts-ignore
+          {cause: error},
+        );
+      }
+    }
+    const cause = new Error('original');
+    const wrapped = new WrappedError(cause) as any;
+    expect(wrapped.cause).toBe(cause);
+  });
+
   it('should always have stack property even without throw', () => {
     // in IE, the stack will be undefined without throw
     // in ZoneAwareError, we will make stack always be