Move device monitors out of //media/capture into //media/device_monitors

media/BUILD.gn

Index: media/BUILD.gn
diff --git a/media/BUILD.gn b/media/BUILD.gn
index 96e6cbed33b30a5fc502c05ff8f4cfc4e161adf6..7786fc94d1f1b8e1c0f1ab1b0be999ddb75f8f87 100644
--- a/media/BUILD.gn
+++ b/media/BUILD.gn
@@ -113,6 +113,10 @@ component("media") {
     "cdm/player_tracker_impl.h",
     "cdm/supported_cdm_versions.cc",
     "cdm/supported_cdm_versions.h",
+    "device_monitors/device_monitor_mac.h",
+    "device_monitors/device_monitor_mac.mm",
+    "device_monitors/system_message_window_win.cc",
+    "device_monitors/system_message_window_win.h",
     "filters/audio_clock.cc",
     "filters/audio_clock.h",
     "filters/audio_renderer_algorithm.cc",
@@ -456,6 +460,14 @@ component("media") {
     ]
   }
 
+  if (use_udev) {
+    deps += [ "//device/udev_linux" ]
+    sources += [
+      "device_monitors/device_monitor_udev.cc",
+      "device_monitors/device_monitor_udev.h",
+    ]
+  }
+
   public_deps += [
     ":media_features",
     ":shared_memory_support",
@@ -526,6 +538,7 @@ test("media_unittests") {
     "cdm/simple_cdm_allocator_unittest.cc",
     "cdm/simple_cdm_buffer.cc",
     "cdm/simple_cdm_buffer.h",
+    "device_monitors/system_message_window_win_unittest.cc",
     "filters/audio_clock_unittest.cc",
     "filters/audio_decoder_selector_unittest.cc",
     "filters/audio_renderer_algorithm_unittest.cc",