Add missing BUILD.gn for third_party/apple_cf

apple_cf is just a header, but we’ve got a BUILD.gn for
third_party/cpp-httplib, which is also just a header.

Change-Id: Ib42c25657b5964678d14682a0a802ebef0e4cb2f
Reviewed-on: https://chromium-review.googlesource.com/c/1489182
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>

third_party/apple_cf/BUILD.gn

@@ -0,0 +1,19 @@
+# Copyright 2019 The Crashpad Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+source_set("apple_cf") {
+  sources = [
+    "CFStreamAbstract.h",
+  ]
+}

util/BUILD.gn

@@ -441,7 +441,10 @@ static_library("util") {
       "Foundation.framework",
       "IOKit.framework",
     ]
-    deps += [ ":mig" ]
+    deps += [
+      ":mig",
+      "../third_party/apple_cf:apple_cf",
+    ]
     include_dirs += [ "$root_build_dir/gen" ]
   }