build: Add Android CI and fix jni/jni_utils version

Android is currently broken in dev due to a change in the jni crate
that's not supported by jni_utils. This was undetected due to lack of CI.

.github/workflows/rust.yml

@@ -14,19 +14,57 @@ jobs:
   build:
     strategy:
       matrix:
-        os:
-          - macOS-latest
-          - ubuntu-latest
-          - windows-latest
+        target:
+          - macos
+          - linux
+          - windows
+          - android
+        include:
+          - target: macos
+            os: macOS-latest
+            cbt: aarch64-apple-darwin
+          - target: linux
+            os: ubuntu-latest
+            cbt: x86_64-unknown-linux-gnu
+          - target: windows
+            os: windows-latest
+            cbt: x86_64-pc-windows-msvc
+          - target: android
+            os: ubuntu-latest
+            cbt: aarch64-linux-android
+
     runs-on: ${{ matrix.os }}
 
+    env:
+      CARGO_BUILD_TARGET: ${{ matrix.cbt }}
+
     steps:
       - uses: actions/checkout@v2
       - name: Install dependencies
         if: ${{ runner.os == 'Linux' }}
         run: |
           sudo apt-get update
           sudo apt-get install libdbus-1-dev
+      - uses: actions/setup-java@v2
+        if: ${{ matrix.target == 'android' }}
+        with:
+          distribution: 'zulu'
+          java-version: '17'
+      - name: Setup NDK
+        if: ${{ matrix.target == 'android' }}
+        uses: nttld/setup-ndk@v1
+        id: setup-ndk
+        with:
+          ndk-version: r25b
+          local-cache: true
+      - name: rust toolchain
+        if: ${{ matrix.target == 'android' }}
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          target: aarch64-linux-android
+          toolchain: stable
+          override: true
       - name: Check
         run: cargo check --all --bins --examples
       - name: Check without default features

Cargo.toml

@@ -41,7 +41,7 @@ dbus = "0.9.7"
 bluez-async = "0.7.2"
 
 [target.'cfg(target_os = "android")'.dependencies]
-jni = "0.21.1"
+jni = "0.19.0"
 once_cell = "1.19.0"
 jni-utils = "0.1.1"