Fix an unintentional switch-case fall-through

This is a follow up CL to my previous CL [1], which introduced a
classical fall through bug due to a missing return statement.

 [1]: Ic614f112f960382280acd8891b3af56d47679f08
      ce82eb2d86

Test: Manually made sure that calling
      InputConnection#performPrivateCommand() no longer causes
      IllegalStateException("Already recycled.").
Bug: 35079353
Fixes: 35681994
Change-Id: I9aa3c0497385e053718d829aad49495771b22b59

core/java/com/android/internal/view/IInputConnectionWrapper.java

@@ -496,6 +496,7 @@ public abstract class IInputConnectionWrapper extends IInputContext.Stub {
                 } finally {
                     args.recycle();
                 }
+                return;
             }
             case DO_REQUEST_UPDATE_CURSOR_ANCHOR_INFO: {
                 SomeArgs args = (SomeArgs)msg.obj;