Notes for Android 10.x

Initial PR: #773.

While making this release, Google has made a lot of changes which affected the development:

1. Google has removed the Trusted Face feature for security reasons (see this post). We've removed the corresponding code for the FaceDetect and FaceUnlock for all platforms.
2. Now we have /system_root in recovery as the main mountpoint instead of /system, so we had to adapt mounting scripts to properly detect that.
3. Pixel Launcher now requires a system setting to be allowed as the main homescreen app, so in order for it to work, we also had to include an overlay to set it as the default launcher app. Same applies to the Digital Wellbeing, Actions Services and Dialer apps have their own overlays now as well.
4. Pixel Launcher now requires Actions Services since it's using it now as the provider for the user app recommendations.
5. Webview implementation changed again in Q - see this article. Because of this, now we additionally ship the TrichromeLibrary which has to match the versions of the Chrome and Webview apps. For now this is ARM and ARM64-only, but once we find an implementation for this for x86 and x86_64 packages, this will be added there as well.

Apart from that, there are still a few bugs: fixed now

• Photos app crashing
• Using Pixel Launcher with Q gesture system will result in FC
• Voice setup doesn't work for some during the initial setup process