Remove recommendation to pin annotation-experimental to version 1.2.0

This was intended to avoid bringing in a transitive dependency on the
Kotlin standard library, but Gradle no longer flags lint errors on
`@RequiresOptIn` violations with `annotation-experimental:1.2.0` (1.3.0
is needed), making this recommendation dangerous. See also
https://issuetracker.google.com/310651921.

PiperOrigin-RevId: 582276430
(cherry picked from commit aa1ec98)

Author: icbaker

RELEASENOTES.md

@@ -25,11 +25,8 @@ This release includes the following changes since the
         `PlayerView.setShowPlayButtonIfPlaybackIsSuppressed(false)` or
         `MediaSession.Builder.setShowPlayButtonIfPlaybackIsSuppressed(false)`
         ([#11213](https://github.com/google/ExoPlayer/issues/11213)).
-    *   Upgrade `androidx.annotation:annotation-experimental` to `1.3.1`. This
-        also introduces a transitive dependency on the Kotlin standard library
-        from `media3-common`. Apps can
-        [downgrade to remove this dependency if they want](https://developer.android.com/guide/topics/media/exoplayer/shrinking#remove-kotlin-dep).
-        Fixes https://issuetracker.google.com/251172715.
+    *   Upgrade `androidx.annotation:annotation-experimental` to `1.3.1` to fix
+        https://issuetracker.google.com/251172715.
     *   Move `ExoPlayer.setAudioAttributes` to the `Player` interface.
 *   ExoPlayer:
     *   Fix seeking issues in AC4 streams caused by not identifying decode-only

demos/main/build.gradle

@@ -72,17 +72,6 @@ android {
 dependencies {
     compileOnly 'org.checkerframework:checker-qual:' + checkerframeworkVersion
     implementation 'androidx.annotation:annotation:' + androidxAnnotationVersion
-    // Demonstrate downgrading the annotation-experimental version to avoid
-    // transitively depending on the Kotlin standard library (which was
-    // introduced as a dependency in annotation-experimental:1.3.0). This demo
-    // app still depends on Kotlin via the IMA extension and UI modules, but
-    // this shows how an app can avoid the Kotlin dependency if they don't use
-    // these modules.
-    implementation('androidx.annotation:annotation-experimental') {
-        version {
-            strictly '1.2.0'
-        }
-    }
     implementation 'androidx.appcompat:appcompat:' + androidxAppCompatVersion
     implementation 'androidx.multidex:multidex:' + androidxMultidexVersion
     implementation 'com.google.android.material:material:' + androidxMaterialVersion