Added Android emulator snapshotting to improve start-up performance

.github/workflows/android.yml

@@ -13,13 +13,13 @@ jobs:
     name: "Compile all sources"
 
     steps:
-    - name: checkout
+    - name: Checkout project
       uses: actions/checkout@v2
       with:
         fetch-depth: 0
         submodules: recursive
 
-    - name: set up JDK 11
+    - name: Set up JDK 11
       uses: actions/setup-java@v2
       with:
         java-version: '11'
@@ -50,13 +50,13 @@ jobs:
     runs-on: macos-latest
 
     steps:
-    - name: checkout
+    - name: Checkout project
       uses: actions/checkout@v2
       with:
         fetch-depth: 0
         submodules: recursive
 
-    - name: set up JDK 11
+    - name: Set up JDK 11
       uses: actions/setup-java@v2
       with:
         java-version: '11'
@@ -91,17 +91,17 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        api-level: [ 15, 20, 24, 30 ]
+        api-level: [ 15, 21, 24, 31 ]
         target: [ default, google_apis ]
 
     steps:
-    - name: checkout
+    - name: Checkout project
       uses: actions/checkout@v2
       with:
         fetch-depth: 0
         submodules: recursive
 
-    - name: set up JDK 11
+    - name: Set up JDK 11
       uses: actions/setup-java@v2
       with:
         java-version: '11'
@@ -114,6 +114,26 @@ jobs:
         path: build
         key: build-${{ github.sha }}
 
+    - name: AVD cache
+      uses: actions/cache@v2
+      id: avd-cache
+      with:
+        path: |
+          ~/.android/avd/*
+          ~/.android/adb*
+        key: avd-${{ matrix.api-level }}-${{ matrix.target }}
+
+    - name: Create AVD and generate snapshot for caching
+      if: steps.avd-cache.outputs.cache-hit != 'true'
+      uses: reactivecircus/android-emulator-runner@v2
+      with:
+        api-level: ${{ matrix.api-level }}
+        target: ${{ matrix.target }}
+        force-avd-creation: false
+        emulator-options: -no-window -gpu swiftshader_indirect -noaudio -no-boot-anim -camera-back none
+        disable-animations: false
+        script: echo "Generated AVD snapshot for caching."
+
     - name: Run Instrumented Tests
       uses: reactivecircus/android-emulator-runner@v2
       with:
@@ -121,6 +141,9 @@ jobs:
         target: ${{ matrix.target }}
         arch: x86
         profile: Nexus 6
+        force-avd-creation: false
+        emulator-options: -no-snapshot-save -no-window -gpu swiftshader_indirect -noaudio -no-boot-anim -camera-back none
+        disable-animations: true
         script: ./gradlew connectedCheck --stacktrace
 
     - name: Save successful debug APK