Migrated GN target rtpcat.

BUG=6162

Review-Url: https://codereview.webrtc.org/2202193002
Cr-Commit-Position: refs/heads/master@{#13605}

webrtc/modules/audio_coding/BUILD.gn

@@ -1317,6 +1317,20 @@ if (rtc_include_tests) {
     ]
   }
 
+  executable("rtpcat") {
+    testonly = true
+
+    sources = [
+      "neteq/tools/rtpcat.cc",
+    ]
+
+    deps = [
+      "../../system_wrappers:system_wrappers_default",
+      "../../test:rtp_test_utils",
+      "//testing/gtest",
+    ]
+  }
+
   executable("rtp_analyze") {
     testonly = true
 

webrtc/modules/audio_coding/neteq/neteq_tests.gypi

@@ -131,6 +131,7 @@
       'dependencies': [
         '<(DEPTH)/testing/gtest.gyp:gtest',
         '<(webrtc_root)/test/test.gyp:rtp_test_utils',
+        '<(webrtc_root)/system_wrappers/system_wrappers.gyp:system_wrappers_default',
       ],
       'sources': [
         'tools/rtpcat.cc',