Add screenshots support for Flutter (#5745)

Author: marandaneto

src/platform-includes/enriching-events/attach-screenshots/flutter.mdx

@@ -0,0 +1,19 @@
+```dart
+import 'package:flutter/widgets.dart';
+import 'package:sentry_flutter/sentry_flutter.dart';
+
+Future<void> main() async {
+  await SentryFlutter.init(
+    (options) {
+      options.dsn = '___PUBLIC_DSN___';
+      options.attachScreenshot = true;
+    },
+    appRunner: () => runApp(
+      // Wrap your app widget with the [SentryScreenshotWidget] widget.
+      SentryScreenshotWidget(
+        child: MyApp(),
+      ),
+    ),
+  );
+}
+```

src/platform-includes/getting-started-primer/android.mdx

@@ -39,6 +39,7 @@ The SDK builds a crash report that persists to disk and tries to send the report
     - Distributed tracing through [OkHttp](/platforms/android/configuration/integrations/okhttp/) and [Apollo](/platforms/android/configuration/integrations/apollo/) integrations
 - [Application Not Responding (ANR)](/platforms/android/configuration/app-not-respond/) reported if the application is blocked for more than five seconds
 - [HTTP Client Errors](/platforms/android/configuration/integrations/okhttp/#http-client-errors)
+- [Screenshot attachments for errors](/platforms/android/enriching-events/screenshots/)
 - Code samples provided in both Kotlin and Java as the Android SDK uses both languages
 - We provide a [sample application](https://github.com/getsentry/sentry-java/tree/master/sentry-samples/sentry-samples-android) for our Android users
 - Our [video tutorial](/platforms/android/android-video/) visually demonstrates how to set up our SDK

src/platform-includes/getting-started-primer/apple.mdx

@@ -33,3 +33,4 @@
   - <PlatformLink to="/performance/instrumentation/automatic-instrumentation/#user-interaction-tracing">User Interaction</PlatformLink> transactions for UI clicks (experimental)
 - [Attachments](/platforms/apple/enriching-events/attachments/) enrich your event by storing additional files, such as config or log files
 - [User Feedback](/platforms/apple/enriching-events/user-feedback/) provides the ability to collect user information when an event occurs
+- [Screenshot attachments for errors](/platforms/apple/guides/ios/enriching-events/screenshots/)

src/platform-includes/getting-started-primer/flutter.mdx

@@ -29,5 +29,6 @@ Features:
   - [Slow and frozen frames](/platforms/flutter/performance/instrumentation/automatic-instrumentation/#slow-and-frozen-frames)
   - [AssetBundle Instrumentation](/platforms/flutter/performance/instrumentation/automatic-instrumentation/#assetbundle-instrumentation)
 - [Logging Integration](/platforms/dart/configuration/integrations/logging)
+- [Screenshot attachments for errors](/platforms/flutter/enriching-events/screenshots/)
 - Limited support for Flutter Web, Windows, and Linux
 - Under the hood the SDK relies on the [Dart SDK](/platforms/dart/); the minimum required version is `2.12.0` and Flutter SDK version is `1.17.0`.

src/platforms/common/configuration/options.mdx

@@ -413,7 +413,7 @@ This is the maximum number of properties or entries that will be included in any
 
 </ConfigKey>
 
-<ConfigKey name="attach-screenshot" supported={["android", "apple.ios", "unity", "dotnet.xamarin"]}>
+<ConfigKey name="attach-screenshot" supported={["android", "apple.ios", "unity", "dotnet.xamarin", "flutter"]}>
 
 Takes a screenshot of the application when an error happens and includes it as an attachment.
 Learn more about enriching events with screenshots in our <PlatformLink to="/enriching-events/screenshots/">Screenshots documentation</PlatformLink>.

src/platforms/common/enriching-events/screenshots.mdx

@@ -8,6 +8,7 @@ supported:
   - unity
   - dotnet.xamarin
   - javascript.electron
+  - flutter
 notSupported:
   - apple.macos
   - apple.tvos