Add missing header files to GN files (4 of N)

ui/gfx/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/ui.gni")
 import("//device/vr/features/features.gni")
 import("//testing/test.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 
 if (is_android) {
@@ skipping 271 matching lines @@
   } else {
     # We don't support RenderText on these platforms.
   }
 
   if (is_android && enable_vr) {
     sources -= [
       "platform_font_android.cc",
       "text_utils_android.cc",
     ]
     set_sources_assignment_filter([])
-    sources += [ "platform_font_linux.cc" ]
+    sources += [
+      "platform_font_linux.cc",
+      "platform_font_linux.h",
+    ]
     set_sources_assignment_filter(sources_assignment_filter)
   }
 
   # iOS.
   if (is_ios) {
     set_sources_assignment_filter([])
     sources += [ "scoped_cg_context_save_gstate_mac.h" ]
     set_sources_assignment_filter(sources_assignment_filter)
   } else {
     deps += [
@@ skipping 461 matching lines @@
 
 fuzzer_test("color_transform_fuzztest") {
   sources = [
     "color_transform_fuzzer.cc",
   ]
   deps = [
     ":gfx",
   ]
   libfuzzer_options = [ "max_len=1024" ]
 }