GN: add the Android support v17 leanback library target

build/secondary/third_party/android_tools/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/android/rules.gni")
 
 config("cpu_features_include") {
   include_dirs = [ "ndk/sources/android/cpufeatures" ]
 }
 
@@ skipping 104 matching lines @@
     ":android_support_v13_java",
     ":android_support_v7_mediarouter_java",
     ":google_play_services_default_resources",
     ":legacy_http_javalib",
   ]
   proguard_preprocess = true
   proguard_config = "//third_party/android_tools/proguard.flags"
   jar_path = "$android_sdk_root/extras/google/google_play_services/libproject/google-play-services_lib/libs/google-play-services.jar"
 }
 
+android_resources("android_support_v17_leanback_resources") {
+  v14_skip = true
+  resource_dirs =
+      [ "$android_sdk_root/extras/android/support/v17/leanback/res" ]
+  custom_package = "android.support.v17.leanback"
+}
+
+android_java_prebuilt("android_support_v17_leanback_java") {
+  deps = [
+    ":android_support_v17_leanback_resources",
+    ":android_support_v7_recyclerview_java",
+  ]
+  jar_path = "$android_sdk_root/extras/android/support/v17/leanback/libs/android-support-v17-leanback.jar"
+}
+
 # TODO(jbudorick): Remove this once net_java_test_support no longer needs it.
 android_java_prebuilt("legacy_http_javalib") {
   jar_path = "$android_sdk/optional/org.apache.http.legacy.jar"
 }