Use std::unordered_map in KeyCharacterMap

Previously, KeyedVector was used in KeyCharacterMap. Convert this to the
std::unordered_map.

Bug: 278299254
Test: m checkinput
Test: m libinput_tests && $ANDROID_HOST_OUT/nativetest64/libinput_tests/libinput_tests
Change-Id: I643aa8cc8ae0c68ade4d11d02e34be64faf7f157
diff --git a/services/inputflinger/Android.bp b/services/inputflinger/Android.bp
index e04481c..69df45b 100644
--- a/services/inputflinger/Android.bp
+++ b/services/inputflinger/Android.bp
@@ -224,6 +224,9 @@
         "libinputservice_test",
         "Bug-115739809",
         "StructLayout_test",
+        // currently unused, but still must build correctly
+        "inputflinger",
+        "libinputflingerhost",
 
         // native fuzzers
         "inputflinger_latencytracker_fuzzer",