GN: Tighten up test target visibility + refactorings

webrtc/modules/video_coding/BUILD.gn

Index: webrtc/modules/video_coding/BUILD.gn
diff --git a/webrtc/modules/video_coding/BUILD.gn b/webrtc/modules/video_coding/BUILD.gn
index 9b611bb72f6ded94a411467cf3066225df407321..821e3960cdd046ce14b4ba5519387d8ceb73e8a2 100644
--- a/webrtc/modules/video_coding/BUILD.gn
+++ b/webrtc/modules/video_coding/BUILD.gn
@@ -379,6 +379,12 @@ if (rtc_include_tests) {
   rtc_source_set("video_coding_modules_tests") {
     testonly = true
 
+    # Skip restricting visibility on mobile platforms since the tests on those
+    # gets additional generated targets which would require many lines here to
+    # cover (which would be confusing to read and hard to maintain).
+    if (!is_android && !is_ios) {
+      visibility = [ "//webrtc/modules:modules_tests" ]
+    }
     sources = [
       "codecs/h264/test/h264_impl_unittest.cc",
       "codecs/test/videoprocessor_integrationtest.cc",
@@ -479,6 +485,13 @@ if (rtc_include_tests) {
 
   rtc_source_set("video_coding_unittests") {
     testonly = true
+
+    # Skip restricting visibility on mobile platforms since the tests on those
+    # gets additional generated targets which would require many lines here to
+    # cover (which would be confusing to read and hard to maintain).
+    if (!is_android && !is_ios) {
+      visibility = [ "//webrtc/modules:modules_unittests" ]
+    }
     sources = [
       "codecs/test/packet_manipulator_unittest.cc",
       "codecs/test/stats_unittest.cc",