More speaker notes about Android (#1501)

Helps with https://github.com/google/comprehensive-rust/issues/1083

src/android.md

@@ -1,10 +1,25 @@
 # Welcome to Rust in Android
 
-Rust is supported for native platform development on Android. This means that
-you can write new operating system services in Rust, as well as extending
-existing services.
+Rust is supported for system software on Android. This means that
+you can write new services, libraries, drivers or even firmware in Rust
+(or improve existing code as needed).
 
 > We will attempt to call Rust from one of your own projects today. So try to
 > find a little corner of your code base where we can move some lines of code to
 > Rust. The fewer dependencies and "exotic" types the better. Something that
 > parses some raw bytes would be ideal.
+
+<details>
+
+The speaker may mention any of the following given the increased use of Rust
+in Android:
+
+- Service example: [DNS over HTTP](https://security.googleblog.com/2022/07/dns-over-http3-in-android.html)
+
+- Libraries: [Rutabaga Virtual Graphics Interface](https://crosvm.dev/book/appendix/rutabaga_gfx.html)
+
+- Kernel Drivers: [Binder](https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-0-08ba9197f637@google.com/)
+
+- Firmware: [pKVM firmware](https://security.googleblog.com/2023/10/bare-metal-rust-in-android.html)
+
+</details>

src/android/build-rules.md

@@ -3,7 +3,7 @@
 The Android build system (Soong) supports Rust via a number of modules:
 
 | Module Type       | Description                                                                                        |
-|-------------------|----------------------------------------------------------------------------------------------------|
+| ----------------- | -------------------------------------------------------------------------------------------------- |
 | `rust_binary`     | Produces a Rust binary.                                                                            |
 | `rust_library`    | Produces a Rust library, and provides both `rlib` and `dylib` variants.                            |
 | `rust_ffi`        | Produces a Rust C library usable by `cc` modules, and provides both static and shared variants.    |
@@ -14,3 +14,21 @@ The Android build system (Soong) supports Rust via a number of modules:
 | `rust_bindgen`    | Generates source and produces a Rust library containing Rust bindings to C libraries.              |
 
 We will look at `rust_binary` and `rust_library` next.
+
+<details>
+
+Additional items speaker may mention:
+
+- cargo is not optimized for multi-language repos, and also downloads packages from the internet.
+
+- For compliance and performance, Android must have crates in-tree.  It must also interop with C/C++/Java code.  Soong fills that gap.
+
+- Soong has many similarities to Bazel, which is the open-source variant of Blaze (used in google3).
+
+- There is a plan to transition [Android](https://source.android.com/docs/setup/build/bazel/introduction), [ChromeOS](https://chromium.googlesource.com/chromiumos/bazel/), and [Fuchsia](https://source.android.com/docs/setup/build/bazel/introduction) to Bazel.
+
+- Learning Bazel-like build rules is useful for all Rust OS developers.
+
+- Fun fact: Data from Star Trek is a Soong-type Android.
+
+</details>

src/android/setup.md

@@ -1,7 +1,7 @@
 # Setup
 
-We will be using an Android Virtual Device to test our code. Make sure you have
-access to one or create a new one with:
+We will be using a Cuttlefish Android Virtual Device to test our code. Make sure you
+have access to one or create a new one with:
 
 ```shell
 source build/envsetup.sh
@@ -11,3 +11,13 @@ acloud create
 
 Please see the [Android Developer
 Codelab](https://source.android.com/docs/setup/start) for details.
+
+<details>
+
+Key points:
+
+- Cuttlefish is a reference Android device designed to work on generic Linux desktops.  MacOS support is also planned.
+
+- The Cuttlefish system image maintains high fidelity to real devices, and is the ideal emulator to run many Rust use cases.
+
+</details>