Implement GetTotalReceivedBytes() for StreamSocket

GetTotalReceivedBytes() returns the number of bytes
read from the network. Currently, only TCPClientSocket
implements GetTotalReceivedBytes().

Tests are in ssl_client_socket_unittest.cc.

Right now GetTotalReceivedBytes() is not plumbed to the
higher layers. Once that's done, this will help us in
precisely computing the network bytes used by a request.

BUG=537754

Review URL: https://codereview.chromium.org/1343563002

Cr-Commit-Position: refs/heads/master@{#354092}
diff --git a/net/socket/unix_domain_client_socket_posix.cc b/net/socket/unix_domain_client_socket_posix.cc
index 5e55a92d..d8cbfaf 100644
--- a/net/socket/unix_domain_client_socket_posix.cc
+++ b/net/socket/unix_domain_client_socket_posix.cc
@@ -152,6 +152,11 @@
   out->clear();
 }
 
+int64_t UnixDomainClientSocket::GetTotalReceivedBytes() const {
+  NOTIMPLEMENTED();
+  return 0;
+}
+
 int UnixDomainClientSocket::Read(IOBuffer* buf, int buf_len,
                                  const CompletionCallback& callback) {
   DCHECK(socket_);