GitLab

Android AAPT 21+ will automatically move attributes to a version
of the XML file with -vXX resource qualifier. So we no longer need
our generate_v14_compatible_resources.py script.

But AAPT only drops the attributes, so if we don't use our script,
we need to put left/right in addition to start/end in our layout xmls.

The plan is, disabling our script for Android support library and
keep using for ourselves, until we can drop the script entirely
when we discontinue support for JB.

TBR=cjhopman@chromium.org
BUG=487391

Review URL: https://codereview.chromium.org/1136953009

Cr-Commit-Position: refs/heads/master@{#329947}