Etar: Add GitHub actions build workflow

Change-Id: I13b49a7690184250223d48ec9742446939ca8e83

Author: luk1337

.github/workflows/build.yml

@@ -0,0 +1,16 @@
+name: build
+
+on: [push, pull_request, workflow_dispatch]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout repo
+      uses: actions/checkout@v4
+      with:
+        submodules: true
+
+    - name: Build
+      uses: ./.github/workflows/build

.github/workflows/build/action.yml

@@ -0,0 +1,21 @@
+name: build
+
+runs:
+    using: composite
+
+    steps:
+    - name: Setup JDK 17
+      uses: actions/setup-java@v4
+      with:
+        distribution: 'zulu'
+        java-version: 17
+        cache: 'gradle'
+
+    - name: Generate Android.bp
+      shell: bash
+      run: |
+        ./gradlew app:generateBp
+        if [[ ! -z $(git status -s) ]]; then
+          git status
+          exit -1
+        fi

.github/workflows/gerrit.yml

@@ -0,0 +1,30 @@
+name: gerrit checks
+
+on:
+  workflow_dispatch:
+    inputs:
+      ref:
+        type: string
+      gerrit-ref:
+        type: string
+      change:
+        type: string
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: lineageos-infra/fetch-gerrit-change@main
+      with:
+        gerrit-ref: ${{ inputs.gerrit-ref }}
+        ref: ${{ inputs.ref }}
+
+    - name: Build
+      uses: ./.github/workflows/build
+
+    - uses: lineageos-infra/gerrit-vote@main
+      if: always()
+      with:
+        auth: ${{ secrets.GERRIT_VOTE_CREDS }}
+        change: ${{ inputs.change }}
+        ref: ${{ inputs.ref }}