Make GN build screenshare_loopback

webrtc/BUILD.gn

Index: webrtc/BUILD.gn
diff --git a/webrtc/BUILD.gn b/webrtc/BUILD.gn
index 88c4e09c72af1cb5e9d56fb3651888a31d32c6c3..cbb7659a63d9fe9c81606dc7c966b50b4165ea57 100644
--- a/webrtc/BUILD.gn
+++ b/webrtc/BUILD.gn
@@ -743,6 +743,35 @@ if (rtc_include_tests) {
     }
   }
 
+  rtc_executable("screenshare_loopback") {
+    testonly = true
+    sources = [
+      "test/run_test.h",
+      "video/screenshare_loopback.cc",
+    ]
+
+    if (is_mac) {
+      sources += [ "test/mac/run_test.mm" ]
+    } else {
+      sources += [ "test/run_test.cc" ]
+    }
+    deps = [
+      ":video_quality_test",
+      "system_wrappers:metrics_default",
+      "test:field_trial",
+      "test:test_common",
+      "test:test_renderer",
+      "//testing/gmock",
+      "//testing/gtest",
+      "//third_party/gflags",
+    ]
+    if (is_clang && !is_nacl) {
+      # Suppress warnings from Chrome's Clang plugins.
+      # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
+      suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
+    }
+  }
+
   rtc_test("webrtc_perf_tests") {
     testonly = true
     configs += [ ":rtc_unittests_config" ]