make gflags command line parser optional

BUG=libyuv:691
TEST=gn gen out/Release "--args=is_debug=false target_cpu=\"x64\" libyuv_include_tests=true"

Change-Id: Ib481189be884c34d9bbc30bfcf71c7969c6f4dae
Reviewed-on: https://chromium-review.googlesource.com/452736
Reviewed-by: Frank Barchard <fbarchard@google.com>
Commit-Queue: Frank Barchard <fbarchard@google.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 4f56cdc2..bcb66b6d 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -9,6 +9,11 @@
 import("libyuv.gni")
 import("//testing/test.gni")
 
+declare_args() {
+  # Set to false to disable building with gflags.
+  libyuv_use_gflags = true
+}
+
 config("libyuv_config") {
   include_dirs = [ "include" ]
   if (is_android && current_cpu == "arm64") {
@@ -231,9 +236,14 @@ if (libyuv_include_tests) {
     deps = [
       ":libyuv",
       "//testing/gtest",
-      "//third_party/gflags",
     ]
 
+    defines = []
+    if (libyuv_use_gflags) {
+      defines += [ "LIBYUV_USE_GFLAGS" ]
+      deps += [ "//third_party/gflags" ]
+    }
+
     configs += [ ":libyuv_unittest_warnings_config" ]
 
     public_deps = [
@@ -241,8 +251,6 @@ if (libyuv_include_tests) {
     ]
     public_configs = [ ":libyuv_unittest_config" ]
 
-    defines = []
-
     if (is_linux) {
       cflags = [ "-fexceptions" ]
     }