make a simple privacy aware Camera app with HDR+ via the Pixel Visual Core

[thestinger]

We're going to need our own camera app using internal storage to store pictures and exposing them with a document provider. It won't bother with internal support for browsing the pictures which is where a fair bit of the complexity for the AOSP Camera2 app stems from. It can also make sure to avoid adding metadata that's more identifying than the pictures being taken from a given device variant.

The code for still shots can be based on https://github.com/google/pixelvisualcorecamera to take full advantage of modern camera capabilities including having HDR+ on the Pixel Visual Core for the Pixel 2 (XL) and future Pixel devices. It will need support for recording videos too.

It's unclear if we should start from AOSP Camera or from https://github.com/google/pixelvisualcorecamera. AOSP Camera is incredibly over-engineered. We'll definitely strip out support for anything not modern. It didn't even work properly on devices with camera3 API support before we made a tweak to it.

[thestinger]

Blocked by #842 because it's not currently reliable enough and ends up stalling / crashing every 20 still shots or so.

[thestinger]

Blocked by #842 because it's not currently reliable enough and ends up stalling / crashing every 20 still shots or so.