Add send transports to individual webrtc::Call streams.

webrtc/video/send_statistics_proxy_unittest.cc

Index: webrtc/video/send_statistics_proxy_unittest.cc
diff --git a/webrtc/video/send_statistics_proxy_unittest.cc b/webrtc/video/send_statistics_proxy_unittest.cc
index b8088655512e0baec88d2ac480f3add0372a2c57..ae0584232447f795f5f8dcc55632934423726e7d 100644
--- a/webrtc/video/send_statistics_proxy_unittest.cc
+++ b/webrtc/video/send_statistics_proxy_unittest.cc
@@ -22,19 +22,19 @@ namespace webrtc {
 class SendStatisticsProxyTest : public ::testing::Test {
  public:
   SendStatisticsProxyTest()
-      : fake_clock_(1234), avg_delay_ms_(0), max_delay_ms_(0) {}
+      : fake_clock_(1234), config_(GetTestConfig()), avg_delay_ms_(0),
+        max_delay_ms_(0) {}
   virtual ~SendStatisticsProxyTest() {}
 
  protected:
   virtual void SetUp() {
     statistics_proxy_.reset(
         new SendStatisticsProxy(&fake_clock_, GetTestConfig()));
-    config_ = GetTestConfig();
     expected_ = VideoSendStream::Stats();
   }
 
   VideoSendStream::Config GetTestConfig() {
-    VideoSendStream::Config config;
+    VideoSendStream::Config config(nullptr);

[mflodman, 2015/08/28 08:30:17]

Why doesn't this trigger the DCHEK at line 19 in
https://codereview.webrtc.org/1273363005/diff/120001/webrtc/video/transport_a...
?

[the sun, 2015/08/28 08:47:35]

This test doesn't create a VideoSendStream (and subsequently no
TransportAdapter) - just a StatisticsProxy, which doesn't use the
send_transport. One could argue that the StatisticsProxy has no business knowing
about the VideoSendStream::Config, but that is a different matter from the focus
of this CL...

     config.rtp.ssrcs.push_back(17);
     config.rtp.ssrcs.push_back(42);
     config.rtp.rtx.ssrcs.push_back(18);