Move blimp/net/test_common.h/cc to a separate source_set.

blimp/net/BUILD.gn

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 component("blimp_net") {
   sources = [
     "blimp_connection.cc",
     "blimp_connection.h",
     "blimp_message_checkpoint_observer.h",
     "blimp_message_demultiplexer.cc",
@@ skipping 38 matching lines @@
 
   defines = [ "BLIMP_NET_IMPLEMENTATION=1" ]
 
   deps = [
     "//base",
     "//blimp/common/proto",
     "//net",
   ]
 }
 
+source_set("test_support") {
+  testonly = true
+
+  sources = [
+    "blimp_net_test_export.h",
+    "test_common.cc",
+    "test_common.h",
+  ]
+
+  deps = [
+    ":blimp_net",
+    "//blimp/common/proto",
+    "//net:test_support",
+    "//testing/gmock",
+  ]
+}
+
 source_set("unit_tests") {
   testonly = true
 
   sources = [
     "blimp_connection_unittest.cc",
     "blimp_message_demultiplexer_unittest.cc",
     "blimp_message_multiplexer_unittest.cc",
     "blimp_message_pump_unittest.cc",
     "engine_connection_manager_unittest.cc",
     "input_message_unittest.cc",
     "stream_packet_reader_unittest.cc",
     "stream_packet_writer_unittest.cc",
     "tcp_transport_unittest.cc",
-    "test_common.cc",
-    "test_common.h",
   ]
 
   deps = [
     ":blimp_net",
+    ":test_support",
     "//base",
     "//base/test:run_all_unittests",
     "//base/test:test_support",
     "//blimp/common/proto",
     "//net:test_support",
     "//testing/gmock",
     "//testing/gtest",
   ]
 }