Add secret to performance integration tests. (#7169)

* Add secret to performance integration tests.

* Updat pull request path to trigger the GHA.

* Remove pull request condition.

* Remove dev test App GoogleService-Info.plist

* Create README.md

* Fix style.

Author: jeremyjiang-dev

.github/workflows/performance-integration-tests.yml

@@ -33,10 +33,18 @@ jobs:
   # TODO: Remove this job config after completely migrated to public repository.
   performance-integration-tests-public:
     if: github.repository == 'Firebase/firebase-ios-sdk'
+    env:
+      plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
     runs-on: macos-latest
     steps:
     - uses: actions/checkout@v2
     - name: Setup Bundler
       run: scripts/setup_bundler.sh
+    - name: Install Secret GoogleService-Info.plist
+      run: |
+        scripts/decrypt_gha_secret.sh scripts/gha-encrypted/Performance/GoogleService-Info_e2e_autopush.plist.gpg \
+            FirebasePerformance/Tests/FIRPerfE2E/FIRPerfE2EAutopush/GoogleService-Info.plist "$plist_secret"
+        scripts/decrypt_gha_secret.sh scripts/gha-encrypted/Performance/GoogleService-Info_e2e_prod.plist.gpg \
+            FirebasePerformance/Tests/FIRPerfE2E/FIRPerfE2EProd/GoogleService-Info.plist "$plist_secret"
     - name: BuildAndTest # can be replaced with pod lib lint with CocoaPods 1.10
       run: scripts/third_party/travis/retry.sh scripts/build.sh Performance all integration

FirebasePerformance/Tests/FIRPerfE2E/FIRPerfE2EAutopush/GoogleService-Info.plist

@@ -0,0 +1,22 @@
+# [Firebase Performance](https://firebase.google.com/docs/perf-mon/get-started-ios) Development App
+
+## Setup
+
+Download the `GoogleService-Info.plist` file from [Firebase Console](https://console.firebase.google.com/)
+(for whatever Firebase project you have or want to integrate the `dev-app`). For Autopush environment, store the
+`GoogleService-Info.plist` under [Plists/Autopush/FIRPerfTestAppAutopush/](./Plists/Autopush/FIRPerfTestAppAutopush/).
+For Prod environment, project, store the `GoogleService-Info.plist` under [Plists/Prod/FIRPerfTestApp/](./Plists/Prod/FIRPerfTestApp/).
+
+## Build
+
+### Generate project for Prod environment from [FirebasePerformance](../../)
+
+- `sh generate_project.sh -e "prod"`
+
+### Generate project for Autopush environment from [FirebasePerformance](../../)
+
+- `sh generate_project.sh` (or) `sh generate_project.sh -e "autopush"`
+
+## Run
+
+- Select `FirebasePerformance-TestApp` target and device to run the App