Allow building of XFA branch without XFA

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("//testing/test.gni")
-
-pdf_use_skia = false
-
-declare_args() {
-  # On Android there's no system FreeType. On Windows and Mac, only a few
-  # methods are used from it.
-  bundle_freetype = !is_linux
-}
+import("pdfium.gni")
 
 config("pdfium_config") {
   cflags = []
   include_dirs = [ "third_party/freetype/include" ]
   defines = [
     "OPJ_STATIC",
     "PNG_PREFIX",
     "PNGPREFIX_H",
     "PNG_USE_READ_MACROS",
     "V8_DEPRECATION_WARNINGS",
     "_CRT_SECURE_NO_WARNINGS",
   ]
 
   if (pdf_use_skia) {
     defines += [ "_SKIA_SUPPORT_" ]
   }
 
+  if (pdf_enable_xfa) {
+    defines += [ "PDF_ENABLE_XFA" ]
+  }
+
   if (is_linux) {
     if (current_cpu == "x64") {
       defines += [ "_FX_CPU_=_FX_X64_" ]
       cflags += [ "-fPIC" ]
     } else if (current_cpu == "x86") {
       defines += [ "_FX_CPU_=_FX_X86_" ]
     }
   }
 
   if (is_win) {
@@ skipping 66 matching lines @@
     ":fpdfdoc",
     ":fpdftext",
     ":fpdfxfa",
     ":fxcodec",
     ":fxcrt",
     ":fxedit",
     ":fxge",
     ":javascript",
     ":jsapi",
     ":pdfwindow",
-    ":xfa",
   ]
 
+  if (pdf_enable_xfa) {
+    deps += [ ":xfa" ]
+  }
+
   if (is_win) {
     libs += [ "advapi32.lib", "gdi32.lib", "user32.lib" ]
   }
 
   if (is_mac) {
     libs += [ "AppKit.framework", "CoreFoundation.framework" ]
   }
 
   if (bundle_freetype) {
     deps += [ "third_party:freetype" ]
@@ skipping 1357 matching lines @@
     ":pdfium"
   ]
   include_dirs = [
     ".",
     "//v8",
     "//v8/include",
   ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ ":pdfium_config", "//build/config/compiler:no_chromium_code" ]
 }