Initialize FontConfigIPC when zygote is disabled so font fallback works.

content/test/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/chrome_build.gni")
 import("//build/config/chromecast_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
@@ skipping 843 matching lines @@
     ]
 
     libs = [ "oleacc.lib" ]
 
     if (symbol_level != 0) {
       data += [ "$root_out_dir/content_browsertests.exe.pdb" ]
     }
   }
 
   if (is_linux) {
-    sources += [ "../zygote/zygote_browsertest.cc" ]
+    sources += [
+      "../browser/linux_ipc_browsertest.cc",
+      "../zygote/zygote_browsertest.cc",
+    ]
+    deps += [ "//ui/gfx:test_support" ]
   }
 
   if (is_android) {
     if (is_component_build) {
       sources += [ "../browser/android/render_widget_host_connector.cc" ]
     }
     sources += [
       "../browser/accessibility/android_granularity_movement_browsertest.cc",
       "../browser/android/render_widget_host_connector_browsertest.cc",
       "../browser/android/render_widget_host_connector_browsertest.h",
@@ skipping 954 matching lines @@
   if (is_android) {
     deps += [ "//testing/android/native_test:native_test_native_code" ]
   }
 }
 
 group("fuzzers") {
   deps = [
     "//content/test/fuzzer",
   ]
 }