[iOS] Fixes animated gifs incorrectly looping

[zhongwuzw]

Summary

After migrate to new GIF implementation, we need to do some cleanup, before, we already unify the gif loop count between iOS and Android, more details please see #21999, so let's unify it again.

Changelog

[iOS] [Fixed] - Fixes animated gifs incorrectly looping

Test Plan

example gif should repeat playback twice.

        <Image
          style={styles.gif}
          source={{uri: "https://user-images.githubusercontent.com/475235/47662061-77011f00-db57-11e8-904f-a1824912ace9.gif"}}
        />

[osdnk]

Let's try

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[sammy-SC]

Hey @zhongwuzw ,

I think we could simplify this, we could assign loopCount = 0 and then when returning from the function we could return loopCount + 1. This way we get rid of this condition. What do you think?

Thanks!

[zhongwuzw]

@sammy-SC Emm, if we return loopCount + 1, the min value is 1? but we need to return 0 if gifLoopCount exist and its value is 0.

[sammy-SC]

Oh, I see :)

Thanks for fixing this.

[react-native-bot]

This pull request was successfully merged by @zhongwuzw in 6f2e6f1.

^{When will my fix make it into a release? | Upcoming Releases}