In the `testing` guide, there is a section discussing configuring
`fakeAsync()` to handle more macro tasks (e.g.
`HTMLCanvasElement#toBlob()`).
Previously, the corresponding code snippets (some of which were
hard-coded in the guide) were incorrect/incomplete and the associated
tests were broken. This was discovered while enabling docs examples unit
tests in #34374.
This commit fixes the code snippets and associated tests and ensures the
examples used in the guide come from an example app (i.e. are not
hard-coded).
Note: The docs examples unit tests are currently not run on CI. This
will be fixed in #34374.
PR Close#35778
8eb4a9d395