Move things in InputWindowInfo to enum classes

Also introduce a new Flag class to make it possible to deal with flags
while treating the individual flags as part of an enum class in a type
safe manner.

Bug: 160010896
Test: atest inputflinger_tests, atest libinput_tests
Change-Id: I915a1c1e3b31f1c0fd99b83ba5fad7e537cd6f84
diff --git a/services/surfaceflinger/LayerProtoHelper.cpp b/services/surfaceflinger/LayerProtoHelper.cpp
index 0fe1421..dd65cf4 100644
--- a/services/surfaceflinger/LayerProtoHelper.cpp
+++ b/services/surfaceflinger/LayerProtoHelper.cpp
@@ -131,8 +131,12 @@
     }
 
     InputWindowInfoProto* proto = getInputWindowInfoProto();
-    proto->set_layout_params_flags(inputInfo.layoutParamsFlags);
-    proto->set_layout_params_type(inputInfo.layoutParamsType);
+    proto->set_layout_params_flags(inputInfo.flags.get());
+    using U = std::underlying_type_t<InputWindowInfo::Type>;
+    // TODO(b/129481165): This static assert can be safely removed once conversion warnings
+    // are re-enabled.
+    static_assert(std::is_same_v<U, int32_t>);
+    proto->set_layout_params_type(static_cast<U>(inputInfo.type));
 
     LayerProtoHelper::writeToProto({inputInfo.frameLeft, inputInfo.frameTop, inputInfo.frameRight,
                                     inputInfo.frameBottom},