In order to make code consistent across all components scheduling in the background, please migrate the BackgroundSyncLauncher to BackgroundTaskScheduler. Good examples are already available in offline pages and prefetch.

Bonus points: BackgroundSyncLauncher will also work on O after doing so.
 

Code in question:
https://cs.chromium.org/chromium/src/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncher.java

Not sure which component to assign here.