Cleanup FWL Event and Message code.

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index a91feeb5a96db873b220fbed2d587506efdc443e..c6d90365b536e6f99038ca13e0912873ce07c434 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1223,40 +1223,16 @@ if (pdf_enable_xfa) {
       "xfa/fwl/core/cfwl_event.h",
       "xfa/fwl/core/cfwl_eventtarget.cpp",
       "xfa/fwl/core/cfwl_eventtarget.h",
-      "xfa/fwl/core/cfwl_evtcheckstatechanged.cpp",
-      "xfa/fwl/core/cfwl_evtcheckstatechanged.h",
       "xfa/fwl/core/cfwl_evtcheckword.cpp",
       "xfa/fwl/core/cfwl_evtcheckword.h",
-      "xfa/fwl/core/cfwl_evtclick.cpp",
-      "xfa/fwl/core/cfwl_evtclick.h",
-      "xfa/fwl/core/cfwl_evtclose.cpp",
-      "xfa/fwl/core/cfwl_evtclose.h",
-      "xfa/fwl/core/cfwl_evteditchanged.cpp",
-      "xfa/fwl/core/cfwl_evteditchanged.h",
-      "xfa/fwl/core/cfwl_evtkey.cpp",
-      "xfa/fwl/core/cfwl_evtkey.h",
-      "xfa/fwl/core/cfwl_evtkillfocus.cpp",
-      "xfa/fwl/core/cfwl_evtkillfocus.h",
       "xfa/fwl/core/cfwl_evtmouse.cpp",
       "xfa/fwl/core/cfwl_evtmouse.h",
-      "xfa/fwl/core/cfwl_evtmousewheel.cpp",
-      "xfa/fwl/core/cfwl_evtmousewheel.h",
-      "xfa/fwl/core/cfwl_evtpostdropdown.cpp",
-      "xfa/fwl/core/cfwl_evtpostdropdown.h",
-      "xfa/fwl/core/cfwl_evtpredropdown.cpp",
-      "xfa/fwl/core/cfwl_evtpredropdown.h",
       "xfa/fwl/core/cfwl_evtscroll.cpp",
       "xfa/fwl/core/cfwl_evtscroll.h",
       "xfa/fwl/core/cfwl_evtselectchanged.cpp",
       "xfa/fwl/core/cfwl_evtselectchanged.h",
-      "xfa/fwl/core/cfwl_evtsetfocus.cpp",
-      "xfa/fwl/core/cfwl_evtsetfocus.h",
-      "xfa/fwl/core/cfwl_evtsizechanged.cpp",
-      "xfa/fwl/core/cfwl_evtsizechanged.h",
       "xfa/fwl/core/cfwl_evttextchanged.cpp",
       "xfa/fwl/core/cfwl_evttextchanged.h",
-      "xfa/fwl/core/cfwl_evttextfull.cpp",
-      "xfa/fwl/core/cfwl_evttextfull.h",
       "xfa/fwl/core/cfwl_evtvalidate.cpp",
       "xfa/fwl/core/cfwl_evtvalidate.h",
       "xfa/fwl/core/cfwl_form.cpp",