SDK / exoplayer

This type of flicker was visible (at least on my S8) whenever starting
the demo app process (from being properly killed) when other notifications
(e.g. completed download notification) was present.

This change passes whether the service was started as foreground through
the intent, and only applies the show-notification-on-stop hack if it
was. It's only necessary to start as foreground if your app is not already
in the foreground, so it's not necessary to do this from activity/ui
components.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195594930

If an app wants to reconcile its own state with that of a DownloadManager,
it's helpful to know when the DownloadManager has finished restoring any
previously persisted tasks.

Also suppress initial "state changed to paused" listener invocations for
tasks that are immediately started.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195594881

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195593235

- Start before stop
- Release near bottom
- Private after public

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195570480

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195570401

The lint workaround and org.json exclusion aren't needed any more.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195557066

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195555915

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195552434

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195544030

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195511490

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195504064

Also convert them to exposing periods and track groups, like
regular MediaSources do. This gets us much closer to being
able to use standard track selection components during offline
initialization. The helper is responsible for reverse mapping
selected tracks onto physical streams when generating the
download action. This is trivial except for the HLS case, which
is a TODO for now.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195500826

This may be preferable for using custom binary data,
and it's still easy to store Strings if needed.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195486817

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195468987

The old event listener on AdsMediaSource is deprecated, in favor of
reporting in the normal way (via MediaSourceEventListener).

Add AdLoadException with information on what ad/ads failed to load.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195426144

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195421908

- Support handling metadata queries (a.k.a get TrackGroupArray, which contains
Format and associated Metadata) from MetadataRetriever.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195401204

Upstream components may incorrectly clear the interrupted flag and not
propagate an exception when the caching thread is interrupted due to
cancellation. Pass a settable flag down to CacheUtil.cache and check it
frequently so it's not necessary to rely on the interrupted flag.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195371244

This avoids the interrupted flag being lost if the exception
is handled as an IOException.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195366244

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195364299

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195362765

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195358542

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195351640

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195346555

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195317847

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195282481

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195271273

- Made parts of DownloadActions public that were previously hidden.
  This is necessary so that when an app is listening to the
  DownloadManager, it can tell something about the tasks.
- Simplified DownloadActivity some more. The helpers may migrate
  into their corresponding modules at some point, and also be
  converted to return structured TrackGroupArrays rather than a
  flat list of Formats.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195269824

Also add a build rule to simplify the test setup with a custom blacklist.
In addition, the test path pattern are made less specific to capture all the
static nullness tests in the /main/ directories.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195230334

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195203362

This includes only the (hopefully) non-debatable changes for the DASH module
and all needed changes for call into the core library.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195097791

Currently it's possible to copy a master playlist with a URL
that was never present in the original. This change prevents
this, and also moves the key more in line with DASH/SS.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=195065286

A single master version prevents app developers from providing
custom download functionality (because they can't increment the
version). It's also error prone to expect someone modifying the
DASH action to remember to update the ActionFile master version.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194981886

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194961264

Ad load errors will be forwarded as media source load errors in the future
and other ad events are not actually player related to warrant reporting
them as part of playback analytics.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194936656

This was adding a lot of code, and the multiple use cases
for Downloader was pretty confusing (in particular the
ordering of method calls was unclear). It's also not
performant (e.g. it requires loading/parsing manifest(s)
and initialization segments from disk).

In practice I think apps will need to keep a record of
what's offlined in their app's database (or equivalent),
which they can update by registering as a listener on
DownloadManager. This will be done for the demo app in
a subsequent change.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194932876

NORELNOTES=true
NO_BUG

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194932235

- It's much cleaner to split completed/error notification methods.
- Make error notification show the content title in the demo app.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194920507

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194902748

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194882787