Add configuration for disabling stylus button motion events

This adds an option for disabling stylus buttons from being reported as
part of a motion gesture. When disabled, all reported motion events'
button state will not include any stylus buttons. Key events are
unaffected.

Bug: 263256832
Test: atest inputflinger_tests
Change-Id: If9ac98c77e980e6b45cfc012ed04b5541e350ebc
diff --git a/services/inputflinger/tests/FakeInputReaderPolicy.cpp b/services/inputflinger/tests/FakeInputReaderPolicy.cpp
index f755356..bb8a30e 100644
--- a/services/inputflinger/tests/FakeInputReaderPolicy.cpp
+++ b/services/inputflinger/tests/FakeInputReaderPolicy.cpp
@@ -201,6 +201,10 @@
     mConfig.wheelVelocityControlParameters = params;
 }
 
+void FakeInputReaderPolicy::setStylusButtonMotionEventsEnabled(bool enabled) {
+    mConfig.stylusButtonMotionEventsEnabled = enabled;
+}
+
 void FakeInputReaderPolicy::getReaderConfiguration(InputReaderConfiguration* outConfig) {
     *outConfig = mConfig;
 }