Add github actions.

Author: cloudwebrtc

.github/workflows/build.yml

@@ -0,0 +1,29 @@
+name: Build
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  test:
+    name: Test on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-java@v1
+        with:
+          java-version: '12.x'
+      - uses: subosito/flutter-action@v1
+        with:
+          flutter-version: '2.2.3'
+          channel: 'stable'
+      - run: dart pub get
+      - run: dart format lib/ test/ --set-exit-if-changed
+      - run: dart pub run import_sorter:main --no-comments --exit-if-changed
+      - run: dart analyze

.github/workflows/publish.yaml

@@ -0,0 +1,21 @@
+name: Publish plugin
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  publish:
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v1
+      - name: Publish
+        uses: sakebook/actions-flutter-pub-publisher@v1.3.1
+        with:
+          credential: ${{ secrets.CREDENTIAL_JSON }}
+          flutter_package: true
+          skip_test: true
+          dry_run: false