Call callback future listeners on app handler

Calling maybeUpdateLegacyErrorState potentially creates a new legacy playback
state which involves calling player methods. This change makes sure that the call
sites of `maybeUpdateLegacyErrorState` are called on the app thread as enforced by
the library.

PiperOrigin-RevId: 476406282
(cherry picked from commit 74124f48)

libraries/session/src/main/java/androidx/media3/session/MediaLibrarySessionImpl.java

@@ -18,6 +18,7 @@ package androidx.media3.session;
 import static androidx.media3.common.util.Assertions.checkNotNull;
 import static androidx.media3.common.util.Assertions.checkNotNull;
 import static androidx.media3.common.util.Assertions.checkState;
 import static androidx.media3.common.util.Assertions.checkState;
 import static androidx.media3.common.util.Assertions.checkStateNotNull;
 import static androidx.media3.common.util.Assertions.checkStateNotNull;
+import static androidx.media3.common.util.Util.postOrRun;
 import static androidx.media3.session.LibraryResult.RESULT_ERROR_SESSION_AUTHENTICATION_EXPIRED;
 import static androidx.media3.session.LibraryResult.RESULT_ERROR_SESSION_AUTHENTICATION_EXPIRED;
 import static androidx.media3.session.LibraryResult.RESULT_SUCCESS;
 import static androidx.media3.session.LibraryResult.RESULT_SUCCESS;
 import static androidx.media3.session.MediaConstants.ERROR_CODE_AUTHENTICATION_EXPIRED_COMPAT;
 import static androidx.media3.session.MediaConstants.ERROR_CODE_AUTHENTICATION_EXPIRED_COMPAT;
@@ -129,7 +130,7 @@ import java.util.concurrent.Future;
             maybeUpdateLegacyErrorState(result);
             maybeUpdateLegacyErrorState(result);
           }
           }
         },
         },
-        MoreExecutors.directExecutor());
+        (Runnable r) -> postOrRun(getApplicationHandler(), r));
     return future;
     return future;
   }
   }
 
 
@@ -149,7 +150,7 @@ import java.util.concurrent.Future;
             verifyResultItems(result, pageSize);
             verifyResultItems(result, pageSize);
           }
           }
         },
         },
-        MoreExecutors.directExecutor());
+        (Runnable r) -> postOrRun(getApplicationHandler(), r));
     return future;
     return future;
   }
   }
 
 
@@ -164,7 +165,7 @@ import java.util.concurrent.Future;
             maybeUpdateLegacyErrorState(result);
             maybeUpdateLegacyErrorState(result);
           }
           }
         },
         },
-        MoreExecutors.directExecutor());
+        (Runnable r) -> postOrRun(getApplicationHandler(), r));
     return future;
     return future;
   }
   }
 
 
@@ -226,7 +227,7 @@ import java.util.concurrent.Future;
             maybeUpdateLegacyErrorState(result);
             maybeUpdateLegacyErrorState(result);
           }
           }
         },
         },
-        MoreExecutors.directExecutor());
+        (Runnable r) -> postOrRun(getApplicationHandler(), r));
     return future;
     return future;
   }
   }
 
 
@@ -246,7 +247,7 @@ import java.util.concurrent.Future;
             verifyResultItems(result, pageSize);
             verifyResultItems(result, pageSize);
           }
           }
         },
         },
-        MoreExecutors.directExecutor());
+        (Runnable r) -> postOrRun(getApplicationHandler(), r));
     return future;
     return future;
   }
   }