Extract test_video_capturer and test_video_capturer_video_track_source

Extract test_video_capturer and test_video_capturer_video_track_source
into a separate targets.

Bug: b/272350185
Change-Id: Iaeefdb58de94d3a25291bfd09c39b3277c18e18a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/299060
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#39672}
diff --git a/test/BUILD.gn b/test/BUILD.gn
index a7cd342..68ae709 100644
--- a/test/BUILD.gn
+++ b/test/BUILD.gn
@@ -22,6 +22,7 @@
       ":test_common",
       ":test_renderer",
       ":test_support",
+      ":test_video_capturer",
       ":video_test_common",
     ]
 
@@ -110,6 +111,21 @@
   ]
 }
 
+rtc_library("test_video_capturer") {
+  testonly = true
+  sources = [
+    "test_video_capturer.cc",
+    "test_video_capturer.h",
+  ]
+  deps = [
+    "../api:scoped_refptr",
+    "../api/video:video_frame",
+    "../api/video:video_rtp_headers",
+    "../media:rtc_media_base",
+    "../rtc_base/synchronization:mutex",
+  ]
+}
+
 rtc_library("video_test_common") {
   visibility = [ "*" ]
   testonly = true