Add Mojo IPC based input-device service.

components/mus/input_devices/BUILD.gn

Index: components/mus/input_devices/BUILD.gn
diff --git a/media/base/ipc/BUILD.gn b/components/mus/input_devices/BUILD.gn
similarity index 50%
copy from media/base/ipc/BUILD.gn
copy to components/mus/input_devices/BUILD.gn
index d665e2ba43aab66902d0d15ed85e83a1f9f2ab39..ad3b1d73031c9ece65bad42c4fffc832d2ff6718 100644
--- a/media/base/ipc/BUILD.gn
+++ b/components/mus/input_devices/BUILD.gn
@@ -2,21 +2,20 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-source_set("ipc") {
+source_set("input_devices") {
   sources = [
-    "media_param_traits.cc",
-    "media_param_traits.h",
-    "media_param_traits_macros.h",
+    "input_device_server.cc",
+    "input_device_server.h",
   ]
 
-  public_deps = [
-    "//ipc",
-  ]
   deps = [
     "//base",
-    "//media",
-    "//ui/gfx/ipc",
-    "//ui/gfx/ipc/geometry",
-    "//ui/gfx/ipc/skia",
+    "//services/shell/public/cpp:sources",
+    "//skia",
+    "//ui/events/devices",
+  ]
+
+  public_deps = [
+    "//components/mus/public/interfaces/input_devices",
   ]
 }