Cleaning up remoting GN build files. Condense the sources.

remoting/signaling/BUILD.gn

Index: remoting/signaling/BUILD.gn
diff --git a/remoting/signaling/BUILD.gn b/remoting/signaling/BUILD.gn
index 2987aeee760a4d7bc142df35fdde660bcc495601..27d08d7c95d9216b7d79c0111e2e4fad137c94be 100644
--- a/remoting/signaling/BUILD.gn
+++ b/remoting/signaling/BUILD.gn
@@ -2,12 +2,26 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//remoting/remoting_srcs.gni")
-
 static_library("signaling") {
-  sources = rebase_path(remoting_srcs_gypi_values.remoting_signaling_sources,
-                        ".",
-                        "//remoting")
+  sources = [
+    "iq_sender.cc",
+    "iq_sender.h",
+    "jid_util.cc",
+    "jid_util.h",
+    "log_to_server.cc",
+    "log_to_server.h",
+    "push_notification_subscriber.cc",
+    "push_notification_subscriber.h",
+    "server_log_entry.cc",
+    "server_log_entry.h",
+    "signal_strategy.h",
+    "xmpp_login_handler.cc",
+    "xmpp_login_handler.h",
+    "xmpp_signal_strategy.cc",
+    "xmpp_signal_strategy.h",
+    "xmpp_stream_parser.cc",
+    "xmpp_stream_parser.h",
+  ]
 
   configs += [
     "//build/config/compiler:no_size_t_to_int_warning",