refactor: eliminate brightray (#15240)

patches/common/chromium/gtk_visibility.patch

@@ -3,18 +3,17 @@ From: Jeremy Apthorp <nornagon@nornagon.net>
 Date: Thu, 20 Sep 2018 17:48:38 -0700
 Subject: gtk_visibility.patch
 
-Allow electron and brightray to depend on GTK in the GN build.
+Allow electron to depend on GTK in the GN build.
 
 diff --git a/build/config/linux/gtk/BUILD.gn b/build/config/linux/gtk/BUILD.gn
-index deae4d3455a8..fd5d906b98b0 100644
+index deae4d3455a8..5f5db2fd6e5e 100644
 --- a/build/config/linux/gtk/BUILD.gn
 +++ b/build/config/linux/gtk/BUILD.gn
-@@ -18,6 +18,8 @@ group("gtk") {
+@@ -18,6 +18,7 @@ group("gtk") {
    visibility = [
      "//chrome/test:interactive_ui_tests",
      "//chrome/test:unit_tests",
 +    "//electron:*",
-+    "//electron/brightray:*",
      "//examples:peerconnection_client",
      "//gpu/gles2_conform_support:gles2_conform_test_windowless",
      "//remoting/host",