Add "assert_no_deps" to gn.vim

Change-Id: Ie1e2984aea84b4b72c564f3fe437ae0148d611c9
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/11260
Commit-Queue: Scott Graham <scottmg@chromium.org>
Reviewed-by: Scott Graham <scottmg@chromium.org>
diff --git a/misc/vim/syntax/gn.vim b/misc/vim/syntax/gn.vim
index 454aacc..79faa70 100644
--- a/misc/vim/syntax/gn.vim
+++ b/misc/vim/syntax/gn.vim
@@ -43,14 +43,15 @@
 
 " Variables
 syn keyword     gnVariable all_dependent_configs allow_circular_includes_from
-syn keyword     gnVariable args asmflags cflags cflags_c cflags_cc cflags_objc
-syn keyword     gnVariable cflags_objcc check_includes complete_static_lib
-syn keyword     gnVariable configs data data_deps defines depfile deps
+syn keyword     gnVariable args asmflags assert_no_deps
+syn keyword     gnVariable cflags cflags_c cflags_cc cflags_objc cflags_objcc
+syn keyword     gnVariable check_includes complete_static_lib configs
+syn keyword     gnVariable data data_deps data_keys defines depfile deps
 syn keyword     gnVariable framework_dirs frameworks include_dirs inputs ldflags
 syn keyword     gnVariable lib_dirs libs output_extension output_name outputs
 syn keyword     gnVariable public public_configs public_deps scripte sources
 syn keyword     gnVariable testonly visibility contents output_conversion rebase
-syn keyword     gnVariable data_keys walk_keys
+syn keyword     gnVariable walk_keys
 hi def link     gnVariable          Keyword
 
 " Strings