Remove obsolete alternative injection method

The previous commit replaced the IInterface instance (the "input"
service) by the InputManager instance (retrieved by
InputManager.getInstance()).

Both define an "injectInputEvent" method, but the alternate version
(probably) does not concern the InputManager.

This reverts commit b7a06278fe.

PR #3190 <https://github.com/Genymobile/scrcpy/pull/3190>

server/src/main/java/com/genymobile/scrcpy/wrappers/InputManager.java

@@ -15,7 +15,6 @@ public final class InputManager {
 
     private final android.hardware.input.InputManager manager;
     private Method injectInputEventMethod;
-    private boolean alternativeInjectInputEventMethod;
 
     private static Method setDisplayIdMethod;
 
@@ -25,12 +24,7 @@ public final class InputManager {
 
     private Method getInjectInputEventMethod() throws NoSuchMethodException {
         if (injectInputEventMethod == null) {
-            try {
-                injectInputEventMethod = manager.getClass().getMethod("injectInputEvent", InputEvent.class, int.class);
-            } catch (NoSuchMethodException e) {
-                injectInputEventMethod = manager.getClass().getMethod("injectInputEvent", InputEvent.class, int.class, int.class);
-                alternativeInjectInputEventMethod = true;
-            }
+            injectInputEventMethod = manager.getClass().getMethod("injectInputEvent", InputEvent.class, int.class);
         }
         return injectInputEventMethod;
     }
@@ -38,10 +32,6 @@ public final class InputManager {
     public boolean injectInputEvent(InputEvent inputEvent, int mode) {
         try {
             Method method = getInjectInputEventMethod();
-            if (alternativeInjectInputEventMethod) {
-                // See <https://github.com/Genymobile/scrcpy/issues/2250>
-                return (boolean) method.invoke(manager, inputEvent, mode, 0);
-            }
             return (boolean) method.invoke(manager, inputEvent, mode);
         } catch (InvocationTargetException | IllegalAccessException | NoSuchMethodException e) {
             Ln.e("Could not invoke method", e);