Moved transport.h from webrtc/ to webrtc/api, created build target and updated dependencies.

webrtc/api/BUILD.gn

Index: webrtc/api/BUILD.gn
diff --git a/webrtc/api/BUILD.gn b/webrtc/api/BUILD.gn
index e2df5262861ab7737f456db7f2252634a9946f1d..9f51b2dc9feb0fe85d38ce4d8879e987a3edfd6e 100644
--- a/webrtc/api/BUILD.gn
+++ b/webrtc/api/BUILD.gn
@@ -28,6 +28,7 @@ rtc_source_set("call_api") {
 
   deps = [
     # TODO(kjellander): Add remaining dependencies when webrtc:4243 is done.
+    ":transport_api",
     "..:webrtc_common",
     "../base:rtc_base_approved",
     "../modules/audio_coding:audio_encoder_interface",
@@ -316,6 +317,13 @@ rtc_source_set("rtc_stats_api") {
   ]
 }
 
+# GYP version: webrtc/api/api.gyp:transport_api
+rtc_source_set("transport_api") {

[ossu, 2016/10/17 14:05:44]

If transport.h is in api/call, shouldn't it be part of the call_api target
instead of being its own target?

[aleloi, 2016/10/17 14:21:56]

I'm not sure, but I think it shouldn't be merged with call_api.
webrtc::Transport is not tightly coupled with the other things in call. It's
used in quite a lot of other places, which do include anything else from call.
Also, I think that splitting up large build targets in small independent
submodules is generally a good thing: it generates less dependencies in the
future and simplifies modularization. WDYT?

[the sun, 2016/10/17 14:38:35]

I was about to agree with Oskar first, but looking through the rest of your CL I
think it should be a separate target - there's no reason for the rtp_rtcp module
to know about ALL of Call, when it just needs Transport.

[ossu, 2016/10/17 14:54:58]

Alright. Should the file still be in call/ then? Or directly under api?

+  sources = [
+    "call/transport.h",
+  ]
+}
+
 if (rtc_include_tests) {
   config("peerconnection_unittests_config") {
     # The warnings below are enabled by default. Since GN orders compiler flags