SDK / exoplayer

This is achieved by adding a BaseMediaSource which keeps a reference count of the
number of times the source has been prepared and forwards to the actual implementations
only once, such that only minimal changes are needed for each media source.

Issue:#3498

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187186691

Up to now we use a boolean "preventListenerNotification" to suppress updates
while other operations are still in progress. This ensures, for example, that
only one initial timeline is issued even for multiple child sources.

As soon as we allow to reuse the same instance, it becomes increasingly difficult
to manage this manual listener notification suppression. Therefore, this change
schedules an update as a new message on the playback thread immediately after the
current message. This way, we also ensure that all simultaneous updates within one
looper message iteration are reported together.

Issue:#3498

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187180342

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187165173

add h263 format support in fourcc codecID

Use the pattern "string literal".equals(something) to prevent NPE …

Add abstract logging methods to EventLogger

replace 'compile' with 'implementation'

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187026802

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187021822

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187021535

The util package is, in practice, for things that are misc enough
to not warrant their own package. If something is deserving of a
package, it's IMO best placed somewhere else (I know you could
argue it's a util, but you could argue that about almost anything
else as well).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187010018

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186999051

AdsMediaSource must be top-level. Currently the (deprecated) ImaAdsMediaSource
can't be used because it prepares its contained AdsMediaSource as a child
source.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186990882

Allow the position to jump on receiving the first presentable input buffer,
if and only if the buffer timestamp differs significantly from what was
expected. This prevents a stuck buffering case for streams that are thought
to start at t=0, but actually start at t=large_value.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186990214

r2.7.0

Allow the position to jump on receiving the first presentable input buffer,
if and only if the buffer timestamp differs significantly from what was
expected. This prevents a stuck buffering case for streams that are thought
to start at t=0, but actually start at t=large_value.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186454715

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186454715

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186305613

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186305613

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186291489

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186291489

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=186200840

Occasionally the player could transition from playing content to playing an ad
after IMA called playAd. The discontinuity triggered faking the content
position, and the fake position was passed to IMA when content resumed causing
the wrong ad group to be loaded. Fix this by only faking the position if the
player transitions before playAd.

Also fix the calculation of the expected ad group index for a postroll ad, and
wait for the player to transition back from ad to content before passing a
content progress update.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185994229

If an exception is thrown in an IMA callback it crashes the process with lots of
logging from WebView (including several stack traces, etc.). This change wraps
ImaAdsLoader code that might throw, skips any remaining ads (as the errors are
not recoverable, in general) and notifies a new load error callback so that the
application can implement its own handling. The intention is to make the loader
robust to unexpected requests from IMA and avoid crashes.

Also handle IMA loading an ad in an ad group that has no available ads. In rare
cases IMA will try to load an ad for which an error was previously notified, so
this drops those load requests allowing playback of the content to continue.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185985850

Issue:#3340

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185973510

All media periods are part of a queue of windows buffered and played by
ExoPlayer. When repeating windows, the current MediaPeriodId is insufficient
to distinguish between the repetitions of the same period. This makes it hard
to see to which media period load events belong to, and it is also difficult to
determine whether two media periods belong to the same logical window or
whether they are part of different repetitions of the same window.

Therefore this change adds a unique sequence number to each window in the
sequence of windows and this sequence number is saved as part of the
MediaPeriodId.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185829509

If there was no preroll and the pending content position was set before the
first midroll, the pending content position was never cleared so loading the ad
was never triggered.

Only set a pending content position if we know that we need to trigger playing
an ad for the current position and IMA will poll for an ad (because there is a
midroll ad group). Clearing the pending content position happens when IMA pauses
content to play the ad.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185818315