InputDevice: return std::optional from getAbsoluteAxisInfo

This also allows us to remove the valid field from RawAbsoluteAxisInfo,
since we can represent "invalid" axes (which usually just meant absent
ones) using std::nullopt.

Test: atest inputflinger_tests
Test: m checkinput
Test: Check "Raw Touch Axes" section of touch input mapper info in
      dumpsys input
Bug: 245989146
Flag: EXEMPT refactor
Change-Id: I045a2e0b61a84657f2f8171c1fee3cc3e331ac86
diff --git a/services/inputflinger/reader/mapper/InputMapper.h b/services/inputflinger/reader/mapper/InputMapper.h
index 2c51448..e5afcc7 100644
--- a/services/inputflinger/reader/mapper/InputMapper.h
+++ b/services/inputflinger/reader/mapper/InputMapper.h
@@ -16,6 +16,8 @@
 
 #pragma once
 
+#include <optional>
+
 #include "EventHub.h"
 #include "InputDevice.h"
 #include "InputListener.h"
@@ -126,10 +128,11 @@
     explicit InputMapper(InputDeviceContext& deviceContext,
                          const InputReaderConfiguration& readerConfig);
 
-    status_t getAbsoluteAxisInfo(int32_t axis, RawAbsoluteAxisInfo* axisInfo);
+    std::optional<RawAbsoluteAxisInfo> getAbsoluteAxisInfo(int32_t axis);
     void bumpGeneration();
 
-    static void dumpRawAbsoluteAxisInfo(std::string& dump, const RawAbsoluteAxisInfo& axis,
+    static void dumpRawAbsoluteAxisInfo(std::string& dump,
+                                        const std::optional<RawAbsoluteAxisInfo>& axis,
                                         const char* name);
     static void dumpStylusState(std::string& dump, const StylusState& state);
 };