Fix BUILD.gn file name.

Typo in 'cfwl_widgetproperties.cpp'.

BUG=599526

Review URL: https://codereview.chromium.org/1851543002
diff --git a/BUILD.gn b/BUILD.gn
index 6780f2b..b0ab4e1 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1109,7 +1109,7 @@
       "xfa/fwl/lightwidget/cfwl_widget.h",
       "xfa/fwl/lightwidget/cfwl_widgetdelegate.cpp",
       "xfa/fwl/lightwidget/cfwl_widgetdelegate.h",
-      "xfa/fwl/lightwidget/cfwl_widgetproperities.cpp",
+      "xfa/fwl/lightwidget/cfwl_widgetproperties.cpp",
       "xfa/fwl/lightwidget/cfwl_widgetproperties.h",
       "xfa/fwl/theme/cfwl_barcodetp.cpp",
       "xfa/fwl/theme/cfwl_barcodetp.h",