Add flag for media controls drawables reuse

MediaControlsDrawables handles whether the flag is enabled and reuses
created drawables.

Flag: com.android.systemui.media_controls_drawables_reuse
Bug: 358402034
Test: build.
Change-Id: Ie9564848f9ce852057d6e3274972e6cfef379e79
diff --git a/packages/SystemUI/aconfig/systemui.aconfig b/packages/SystemUI/aconfig/systemui.aconfig
index 476fd8b..7c0db8d 100644
--- a/packages/SystemUI/aconfig/systemui.aconfig
+++ b/packages/SystemUI/aconfig/systemui.aconfig
@@ -1066,6 +1066,13 @@
 }
 
 flag {
+  name: "media_controls_drawables_reuse"
+  namespace: "systemui"
+  description: "Re-use created media drawables for media controls"
+  bug: "358402034"
+}
+
+flag {
   namespace: "systemui"
   name: "enable_view_capture_tracing"
   description: "Enables view capture tracing in System UI."
@@ -1338,4 +1345,4 @@
   metadata {
     purpose: PURPOSE_BUGFIX
   }
-}
\ No newline at end of file
+}