Move ScreenCapturer 'real' tests out of screen_capturer_unittest.cc.

webrtc/modules/desktop_capture/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/ui.gni")
 import("../../build/webrtc.gni")
@@ skipping 12 matching lines @@
     "desktop_region.h",
     "shared_desktop_frame.cc",
     "shared_desktop_frame.h",
   ]
 
   deps = [
     "../../base:rtc_base",  # TODO(kjellander): Cleanup in bugs.webrtc.org/3806.
   ]
 }
 
+if (rtc_include_tests) {
+  source_set("desktop_capture_test_tools") {
+    testonly = true
+
+    public_deps = [
+      ":desktop_capture",
+    ]
+
+    sources = [
+      "rgba_color.cc",
+      "rgba_color.h",
+      "screen_drawer.cc",
+      "screen_drawer.h",
+      "screen_drawer_linux.cc",
+      "screen_drawer_mac.cc",
+      "screen_drawer_win.cc",
+    ]
+  }
+}
+
 rtc_static_library("desktop_capture") {
   sources = [
     "cropped_desktop_frame.cc",
     "cropped_desktop_frame.h",
     "cropping_window_capturer.cc",
     "cropping_window_capturer.h",
     "cropping_window_capturer_win.cc",
     "desktop_and_cursor_composer.cc",
     "desktop_and_cursor_composer.h",
     "desktop_capture_options.cc",
@@ skipping 131 matching lines @@
     sources = [
       "differ_vector_sse2.cc",
       "differ_vector_sse2.h",
     ]
 
     if (is_posix) {
       cflags = [ "-msse2" ]
     }
   }
 }