Mark XPI driver options as being deprecated

Author: shs96c

java/client/src/org/openqa/selenium/firefox/FirefoxOptions.java

@@ -185,11 +185,19 @@ private void mirror(FirefoxOptions that) {
     if (that.profile != null) { setProfile(that.profile); }
   }
 
+  /**
+   * @deprecated This method will be deleted and will not be replaced.
+   */
+  @Deprecated
   public FirefoxOptions setLegacy(boolean legacy) {
     setCapability(MARIONETTE, !legacy);
     return this;
   }
 
+  /**
+   * @deprecated This method will be deleted and will not be replaced.
+   */
+  @Deprecated
   public boolean isLegacy() {
     return legacy;
   }

java/client/src/org/openqa/selenium/firefox/xpi/XpiDriverService.java

@@ -62,6 +62,10 @@
 import java.util.function.Supplier;
 import java.util.stream.Stream;
 
+/**
+ * @deprecated This class will not be replaced.
+ */
+@Deprecated
 public class XpiDriverService extends FirefoxDriverService {
 
   private static final String NO_FOCUS_LIBRARY_NAME = "x_ignore_nofocus.so";