[firebase_admob] Provide a default MobileAdTargetingInfo for RewardedVideoAd.load()

[kunny]

Description

Provides a default MobileAdTargetingInfo for RewardedVideoAd.load() method to be aligned with MobileAd's implementation as follows:

abstract class MobileAd {
  /// Default constructor, used by subclasses.
  MobileAd({
    @required this.adUnitId,
    MobileAdTargetingInfo targetingInfo,
    this.listener,
  }) : _targetingInfo = targetingInfo ?? const MobileAdTargetingInfo() {
    assert(adUnitId != null && adUnitId.isNotEmpty);
    assert(_allAds[id] == null);
    _allAds[id] = this;
  }
...

Related Issues

• [firebase_admob] PlatformException(no_targeting_info, a null targetingInfo object was provided for rewarded video, null) #44

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Breaking Change

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• Yes, this is a breaking change (please indicate a breaking change in CHANGELOG.md and increment major revision).
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[bparrishMines]

Everything looks good. We just need a test for this? You could probably just add a test in firebase_admob_e2e.dart that makes sure that calling load() without targetingInfo doesn't cause a crash.

[kunny]

@bparrishMines Added a test for RrewardedVideoAd. Please review and let me know whether it's okay or not.

[bparrishMines]

LGTM

Thanks for adding tests! I bumped the version and will merge once the analyze tests pass again.

[bparrishMines]

It looks like the integration tests have stopped passing after I added the version bump. They haven't passed after re-runnning them either. I'll try and see if I can get them to pass before merging.

[bparrishMines]

I'm going to go ahead and merge this since the failing tests seem to be flaking in PRs. I'll revert if this doesn't pass the test on master.