Update compilesdk version of UniversalMediaPlayer

Test: make UniversalMediaPlayer
Change-Id: I73d64334d80989a28d24d4528122c754d6b653e9
Merged-In: I73d64334d80989a28d24d4528122c754d6b653e9
(cherry picked from commit f8b6d271fbf07c23f671c6b3a3387dbf385d4db1)
diff --git a/Android.bp b/Android.bp
index 45a2c07..72f55a7 100644
--- a/Android.bp
+++ b/Android.bp
@@ -21,7 +21,7 @@
 android_app {
     name: "UniversalMediaPlayer",
     min_sdk_version: "24", // TODO(b/123716038) Sync min SDK version with build.gradle
-    sdk_version: "28",
+    sdk_version: "31",
     srcs: [
         "gen/**/*.java", // TODO(b/123702784) Remove gen/ (either generate or remove dependencies)
         "java/**/*.java"