fix(test): add flag to patch jasmine.clock, move fakeAsync/async into original bundle

[JiaLiPassion]

to resolve breaking changes issue of angular/angular#23108

1. delete new zone-fake-async.js and zone-async-testing.js. just add fakeAsync/asynctest into original zone.js/dist/fake-async.js and zone.js/dist/async-test.js.

2. add a flag __zone_symbol__fakeAsyncPatchLock to control whether to patch jasmine.clock() in fakeAsync. By default it is false, so no breaking changes.

3. update .travis to test both patchClock and non patchClock.

@mhevery, please review, I will also update the angular side to remove the breaking changes, thank you!

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So there's good news and bad news.

👍 The good news is that everyone that needs to sign a CLA (the pull request submitter and all commit authors) have done so. Everything is all good there.

😕 The bad news is that it appears that one or more commits were authored or co-authored by someone other than the pull request submitter. We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that here in the pull request.

Note to project maintainer: This is a terminal state, meaning the cla/google commit status will not change from this state. It's up to you to confirm consent of the commit author(s) and merge this pull request when appropriate.