auto: increment master version to 15.0.21

chore: merge beta to master (A15S1)

chore: increment-version.sh for stable

docs(ios): Help for 14.0 features

Co-authored-by: Darcy Wong <darcywong00@users.noreply.github.com>

chore: B14S8 beta to alpha

auto: increment beta version to 14.0.267

fix(windows): Avoid double start during setup

fix(windows): ensure profiles are reinstalled during setup

fix(linux): Fix switching to keyboard in middle of line (#4678)

fix(ios): kbd search now caches publishing data for result

fix(web): allows refresh of currently-loaded model

fix(common/core/web): predictive banner activation logic

The value is not restored for upgrades unless we back it up, because
Setup does not change these settings if they are not present :)

Fixes #4725.

Fixes #4724.

chore(android/app): Migrate launcher icon to adaptive

auto: increment beta version to 14.0.266

Don't re-set context if it changed because the cursor location was
wrong. When the user switches to the EuroLatin keyboard in the
middle of the line, we're getting a wrong cursor location. This will
be fixed with the next keypress, but it leads to the context string
suddenly having more characters added to the front. If we re-set the
context because it's different now we will loose the information we
previously added to the context.

We now compare the end of the string. If the new context string ends
with the old context string we assume that the cursor position got
updated and don't re-set the context.

This fixes #4678.

chore(windows): finalize help

fix(developer): use var not let in definitions

fix(web): first-pass workaround for popup-key corrections

fix(windows): Download keyboard dialog TLS protocol support

Fixes #4716.

We still support Chrome 37 on Android 5.0, which does not permit
use of the `let` keyword in normal conditions.

fix(common/core/web): disambiguation of keys sharing same base key ID

Fixes #4709.