test: update rebuild debounce times to reduce flakiness

Author: clydin

packages/angular_devkit/build_angular/src/browser/specs/rebuild_spec.ts

@@ -8,7 +8,7 @@
 // tslint:disable:no-big-function
 import { Architect } from '@angular-devkit/architect';
 import { TestLogger } from '@angular-devkit/architect/testing';
-import { join, logging, normalize, virtualFs } from '@angular-devkit/core';
+import { join, normalize, virtualFs } from '@angular-devkit/core';
 import { debounceTime, take, takeWhile, tap } from 'rxjs/operators';
 import {
   createArchitect,
@@ -23,7 +23,7 @@ describe('Browser Builder rebuilds', () => {
   const target = { project: 'app', target: 'build' };
   // Rebuild tests are especially sensitive to time between writes due to file watcher
   // behaviour. Give them a while.
-  const rebuildDebounceTime = 3000;
+  const rebuildDebounceTime = 5000;
   let architect: Architect;
 
   beforeEach(async () => {

packages/angular_devkit/build_angular/src/browser/specs/unused-files-warning_spec.ts

@@ -178,7 +178,7 @@ describe('Browser Builder unused files warnings', () => {
 
     await run.output
       .pipe(
-        debounceTime(1000),
+        debounceTime(4000),
         tap(buildEvent => {
           expect(buildEvent.success).toBe(true);
 

packages/angular_devkit/build_angular/src/browser/specs/web-worker_spec.ts

@@ -147,7 +147,7 @@ describe('Browser Builder Web Worker support', () => {
     const { run } = await timer(1000).pipe(
       switchMap(() => architect.scheduleTarget(target, overrides)),
       switchMap(run => run.output.pipe(map(output => ({ run, output })))),
-      debounceTime(500),
+      debounceTime(4000),
       tap(({ output }) => expect(output.success).toBe(true, 'build should succeed')),
       tap(() => {
         switch (phase) {