Add page on the Android sensitive content feature (#12220)

_Description of what this PR is changing or adding, and why:_
Adds page covering the sensitive content protection feature on Android
as it is being released in the next stable version.

_Issues fixed by this PR (if any):_
N/A

_PRs or commits this PR depends on (if any):_
N/A

## Presubmit checklist

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_tiny_, one-word PR, please file an issue instead of a PR.
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pronouns).
- [x] This PR uses [semantic line
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  of 80 characters or fewer.

---------

Co-authored-by: Shams Zakhour (ignore Sfshaza) <[email protected]>

Author: camsim99

src/_data/sidenav.yml

@@ -550,6 +550,8 @@
           permalink: /platform-integration/android/restore-state-android
         - title: Target ChromeOS with Android
           permalink:  /platform-integration/android/chromeos
+        - title: Protect your app's sensitive content
+          permalink: /platform-integration/android/sensitive-content
     - title: iOS
       permalink: /platform-integration/ios
       children:

src/content/platform-integration/android/sensitive-content.md

@@ -0,0 +1,62 @@
+---
+title: Protect your app's sensitive content
+short-title: Sensitive content
+description: >-
+  Learn how to protect sensitive content in your Flutter app.
+---
+
+This feature is available on Android API 35+, and you can try it out by using
+the [`SensitiveContent`] widget. See the guide below for details.
+
+## About the `SensitiveContent` widget
+
+You can use the `SensitiveContent` widget in your app to set the content
+sensitivity of a child `Widget` to one of the following [`ContentSensitivity`]
+values: `notSensitive`, `sensitive`, or `autoSensitive`. The mode that you
+choose helps to determine if the device screen should be obscured
+(blacked out) during media projection to protect users’ sensitive data.
+
+You can have as many `SensitiveContent` widgets in your app as you wish,
+but if _any_ one of those widgets has a `sensitive` content value, then the
+screen will be obscured during media projection. Thus, for most use cases,
+using multiple `SensitiveContent` widgets provides no advantage over having
+one `SensitiveContent` widget in your app’s widget tree. This feature is
+available on Android API 35+ and has no effect on lower API versions and
+other platforms.
+
+:::note
+The `autoSensitive` value isn't supported as of Flutter 3.35 and behaves
+the same as `notSensitive`. See the [Issue #160879][] for more information.
+:::
+
+## Using the `SensitiveContent` widget
+
+Given some content that you want to protect from media screen share
+(for example, a `MySensitiveContent()` widget), you can wrap it with the
+`SensitiveContent` widget as shown in the following example:
+
+```dart
+class MyWidget extends StatelessWidget {
+  ...
+  Widget build(BuildContext context) {
+    return SensitiveContent(
+      sensitivivity: ContentSensitivity.sensitive,
+      child: MySensitiveContent(),
+    );
+  }
+}
+```
+
+When running on Android API 34 and below, the screen will not been obscured
+during media projection. The widget will exist in the tree but has no other
+effect, and you do not need to avoid usages of `SensitiveContent` on platforms
+that do not support this feature.
+
+## For more information
+
+For more information, visit the [`SensitiveContent`][]
+and [`ContentSensitivity`][] API docs.
+
+[`SensitiveContent`]: {{site.api}}/flutter/widgets/SensitiveContent-class.html
+[`ContentSensitivity`]: {{site.api}}/flutter/services/ContentSensitivity.html
+[Issue #160879]: {{site.github}}/flutter/flutter/issues/160879