when software keyboard disappears, main view would not have focus

see method (1) in
spesmilo/electrum#6276 (comment)

see methods (2) and (3) in
spesmilo/electrum#6276 (comment)

see https://developer.android.com/guide/practices/ui_guidelines/icon_design_adaptive

This adds a `--icon-fg` and a `--icon-bg` build option to the sdl2 bootstrap,
that can be used to specify two PNG files to be used as the foreground and background
of an adaptive icon. These will get used if API 26+ is available at runtime.
The existing `--icon` option to specify an icon as a single PNG file is kept, as
- this provides backwards compatibility,
- and even if the new options are used, it might be a good idea to set all three
  options: when running on API <26, the PNG specified via `--icon` gets used.

* ndk >= r22 no longer supports
  - {ndk_dir}/platform
  - {ndk_dir}/sysroot
* add & use
  - ctx.ndk_standalone
  - ctx.ndk_sysroot
  - ctx.ndk_lib_dir
  - ctx.ndk_include_dir
* patch openssl
* add FIXMEs to some recipes
  - nothing should have changed for ndk < r22
  - modifications and/or testing may be needed for ndk >= r22
* CI: mark some packages as broken

see https://docs.gradle.org/3.4/userguide/working_with_files.html#sec:reproducible_archives

Otherwise it seems that both android-qt5 and android-genericndkbuild
packages are built

these should be available through the material style plugin, but these
aren't picked up correctly currently