Update lynx SVN to 15 am: 298ba980a2 am: 721bf2d648

Original change: https://googleplex-android-review.googlesource.com/c/device/google/lynx/+/24392319

Change-Id: I53bed511c818b5f5ad442eacd7418a5815fb91a6
Signed-off-by: Automerger Merge Worker <[email protected]>