Skip unit test if GYP_DEFINES="rtc_use_h264=1" is not set.

Unit test would fail in default configuration (e.g. rtc_use_h264=0), cause it tests instantiating H264 specifics.

BUG=webrtc:6194, webrtc:6198

Review-Url: https://codereview.webrtc.org/2228733004
Cr-Commit-Position: refs/heads/master@{#13929}

webrtc/media/BUILD.gn

@@ -290,6 +290,7 @@ if (rtc_include_tests) {
   test("rtc_media_unittests") {
     testonly = true
 
+    defines = []
     deps = []
     sources = [
       "base/codec_unittest.cc",
@@ -322,6 +323,9 @@ if (rtc_include_tests) {
     ]
     public_configs = [ "..:common_inherited_config" ]
 
+    if (rtc_use_h264) {
+      defines += [ "WEBRTC_USE_H264" ]
+    }
     if (is_win) {
       cflags = [
         "/wd4245",  # conversion from int to size_t, signed/unsigned mismatch.

webrtc/media/engine/webrtcvideoengine2_unittest.cc

@@ -3595,7 +3595,11 @@ TEST_F(WebRtcVideoChannel2Test, GetRtpReceiveParametersCodecs) {
   EXPECT_EQ(kVp9Codec.ToCodecParameters(), rtp_parameters.codecs[1]);
 }
 
+#if defined(WEBRTC_USE_H264)
 TEST_F(WebRtcVideoChannel2Test, GetRtpReceiveFmtpSprop) {
+#else
+TEST_F(WebRtcVideoChannel2Test, DISABLED_GetRtpReceiveFmtpSprop) {
+#endif
   cricket::VideoRecvParameters parameters;
   cricket::VideoCodec kH264sprop1(101, "H264", 640, 400, 15);
   kH264sprop1.SetParam("sprop-parameter-sets", "uvw");

webrtc/media/media.gyp

@@ -294,6 +294,11 @@
             4389,  # signed/unsigned mismatch.
           ],
           'conditions': [
+            ['rtc_use_h264==1', {
+              'defines': [
+                 'WEBRTC_USE_H264'
+              ]
+            }],
             ['OS=="win"', {
               'msvs_settings': {
                 'VCLinkerTool': {