port cfi to gn

tools/gn/substitution_type.cc

Index: tools/gn/substitution_type.cc
diff --git a/tools/gn/substitution_type.cc b/tools/gn/substitution_type.cc
index 2713ee2daf4abdeabc13be42afb2bb5f37b3a642..494a907ec830d8ea417c19419264c7df2cb9d626 100644
--- a/tools/gn/substitution_type.cc
+++ b/tools/gn/substitution_type.cc
@@ -28,6 +28,7 @@ const char* kSubstitutionNames[SUBSTITUTION_NUM_TYPES] = {
   "{{target_out_dir}}",  // SUBSTITUTION_TARGET_OUT_DIR
   "{{target_output_name}}",  // SUBSTITUTION_TARGET_OUTPUT_NAME
 
+  "{{arflags}}",  // SUBSTITUTION_ARFLAGS
   "{{cflags}}",  // SUBSTITUTION_CFLAGS
   "{{cflags_c}}",  // SUBSTITUTION_CFLAGS_C
   "{{cflags_cc}}",  // SUBSTITUTION_CFLAGS_CC
@@ -64,6 +65,7 @@ const char* kSubstitutionNinjaNames[SUBSTITUTION_NUM_TYPES] = {
     "target_out_dir",      // SUBSTITUTION_TARGET_OUT_DIR
     "target_output_name",  // SUBSTITUTION_TARGET_OUTPUT_NAME
 
+    "arflags",       // SUBSTITUTION_ARFLAGS
     "cflags",        // SUBSTITUTION_CFLAGS
     "cflags_c",      // SUBSTITUTION_CFLAGS_C
     "cflags_cc",     // SUBSTITUTION_CFLAGS_CC
@@ -152,6 +154,7 @@ bool IsValidLinkerSubstitution(SubstitutionType type) {
   return IsValidToolSubstutition(type) ||
          type == SUBSTITUTION_LINKER_INPUTS ||
          type == SUBSTITUTION_LINKER_INPUTS_NEWLINE ||
+         type == SUBSTITUTION_ARFLAGS ||
          type == SUBSTITUTION_LDFLAGS ||
          type == SUBSTITUTION_LIBS ||
          type == SUBSTITUTION_OUTPUT_EXTENSION ||