Remove SystemUiProxy#monitorGestureInput() as it's no longer used

Test: compiles and runs locally
Bug: 185266621
Change-Id: I4d40de269007178550cf1a9e9e906018badc6f74
diff --git a/quickstep/src/com/android/quickstep/SystemUiProxy.java b/quickstep/src/com/android/quickstep/SystemUiProxy.java
index 1f332c4..3edce6f 100644
--- a/quickstep/src/com/android/quickstep/SystemUiProxy.java
+++ b/quickstep/src/com/android/quickstep/SystemUiProxy.java
@@ -255,18 +255,6 @@
     }
 
     @Override
-    public Bundle monitorGestureInput(String name, int displayId) {
-        if (mSystemUiProxy != null) {
-            try {
-                return mSystemUiProxy.monitorGestureInput(name, displayId);
-            } catch (RemoteException e) {
-                Log.w(TAG, "Failed call monitorGestureInput: " + name, e);
-            }
-        }
-        return null;
-    }
-
-    @Override
     public void notifyAccessibilityButtonClicked(int displayId) {
         if (mSystemUiProxy != null) {
             try {