Fix XFA GN build

R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1401253002 .
diff --git a/BUILD.gn b/BUILD.gn
index cf07c33..23e9f9a 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -9,7 +9,7 @@
 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
+  pdfium_bundle_freetype = !is_linux
 }
 
 config("pdfium_config") {
@@ -125,8 +125,8 @@
     libs += [ "AppKit.framework", "CoreFoundation.framework" ]
   }
 
-  if (bundle_freetype) {
-    deps += [ "third_party:freetype" ]
+  if (pdfium_bundle_freetype) {
+    deps += [ "third_party:fx_freetype" ]
   } else {
     libs += [ "freetype" ]
   }
diff --git a/third_party/BUILD.gn b/third_party/BUILD.gn
index 27b6023..a6c9520 100644
--- a/third_party/BUILD.gn
+++ b/third_party/BUILD.gn
@@ -5,7 +5,7 @@
 group("third_party") {
   deps = [
     ":bigint",
-    ":freetype",
+    ":fx_freetype",
     ":pdfium_base",
   ]
 }
@@ -30,7 +30,7 @@
   ]
 }
 
-source_set("freetype") {
+source_set("fx_freetype") {
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     "//build/config/compiler:no_chromium_code",