uses-sdk:minSdkVersion 16 cannot be smaller than version 19 declared in library [:firebase_analytics]

Flutterでfirebase_analyticsを導入したところ、Androidでビルドエラーになった。

***/android/app/src/debug/AndroidManifest.xml Error:
    uses-sdk:minSdkVersion 16 cannot be smaller than version 19 declared in library [:firebase_analytics] ***/build/firebase_analytics/intermediates/merged_manifest/debug/AndroidManifest.xml as the library might be using APIs not available in 16
    Suggestion: use a compatible library with a minSdk of at most 16,
        or increase this project's minSdk version to at least 19,
        or use tools:overrideLibrary="io.flutter.plugins.firebase.analytics" to force usage (may lead to runtime failures)

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:processDebugMainManifest'.
> Manifest merger failed : uses-sdk:minSdkVersion 16 cannot be smaller than version 19 declared in library [:firebase_analytics] ***/build/firebase_analytics/intermediates/merged_manifest/debug/AndroidManifest.xml as the library might be using APIs not available in 16
    Suggestion: use a compatible library with a minSdk of at most 16,
        or increase this project's minSdk version to at least 19,
        or use tools:overrideLibrary="io.flutter.plugins.firebase.analytics" to force usage (may lead to runtime failures)

┌─ Flutter Fix ─────────────────────────────────────────────────────────────────────────────────┐
│ The plugin firebase_analytics requires a higher Android SDK version.                          │
│ Fix this issue by adding the following to the file                                            │
│ ***/android/app/build.gradle:                       │
│ android {                                                                                     │
│   defaultConfig {                                                                             │
│     minSdkVersion 19                                                                          │
│   }                                                                                           │
│ }                                                                                             │
│                                                                                               │
│ Note that your app won't be available to users running Android SDKs below 19.                 │
│ Alternatively, try to find a version of this plugin that supports these lower versions of the │
│ Android SDK.                                                                                  │
│ For more information, see:                                                                    │
│ https://docs.flutter.dev/deployment/android#reviewing-the-build-configuration                 │
└───────────────────────────────────────────────────────────────────────────────────────────────┘
Exception: Gradle task assembleDebug failed with exit code 1

記載の通り、minSdkVersionの記述を変えたところ解決した。flutter的には16だがfirebase_analytics的には19以上が必須で、個人的にもっとサポートOSを減らしたいので22に設定した。

android {
  defaultConfig {
      minSdkVersion 22 // もともとは flutter.minSdkVersionだった。
  }
}