Delete TouchState::deviceId

We are doing per-device pointer tracking now, so this CL helps remove
the assumptions around having a single active device.

For now, the behaviour is preserved. In the future, we will not need to
check the currently active device at the TouchState level.

Bug: 211379801
Test: m inputflinger_tests && $ANDROID_HOST_OUT/nativetest64/inputflinger_tests/inputflinger_tests
Change-Id: Ie13e9c93eefc04c2955de3b8a06c9c2da28c9d72
diff --git a/services/inputflinger/dispatcher/TouchedWindow.h b/services/inputflinger/dispatcher/TouchedWindow.h
index e50ede5..81393fc 100644
--- a/services/inputflinger/dispatcher/TouchedWindow.h
+++ b/services/inputflinger/dispatcher/TouchedWindow.h
@@ -53,6 +53,10 @@
      * nullopt.
      */
     std::set<int32_t> getTouchingDeviceIds() const;
+    /**
+     * The ids of devices that are currently touching or hovering.
+     */
+    std::set<int32_t> getActiveDeviceIds() const;
 
     // Pilfering pointers
     bool hasPilferingPointers(int32_t deviceId) const;