GN rules for everything in //mojo

mojo/examples/surfaces_app/BUILD.gn

Index: mojo/examples/surfaces_app/BUILD.gn
diff --git a/mojo/examples/surfaces_app/BUILD.gn b/mojo/examples/surfaces_app/BUILD.gn
index 98a3e5b45c50aecc5c92be133113bdf1ec0cf73c..a929b878b6ead8b81391c84019bd9a4a4cfd2c69 100644
--- a/mojo/examples/surfaces_app/BUILD.gn
+++ b/mojo/examples/surfaces_app/BUILD.gn
@@ -71,6 +71,36 @@ shared_library("child_app") {
   ]
 }
 
+# GYP version: mojo/mojo_examples.gypi:mojo_surfaces_child_gl_app
+shared_library("child_gl_app") {
+  output_name = "mojo_surfaces_child_gl_app"
+
+  deps = [
+    ":bindings",
+    ":util",
+    "//base",
+    "//cc",
+    "//cc/surfaces",
+    "//skia",
+    "//ui/gfx",
+    "//ui/gfx/geometry",
+    "//mojo/common",
+    "//mojo/public/cpp/application:chromium",
+    "//mojo/environment:chromium",
+    "//mojo/examples/sample_app:spinning_cube",
+    "//mojo/services/public/interfaces/geometry",
+    "//mojo/services/public/cpp/geometry",
+    "//mojo/services/public/interfaces/surfaces",
+    "//mojo/services/public/cpp/surfaces",
+  ] + mojo_system_for_shared_library
+
+  sources = [
+    "child_gl_app.cc",
+    "child_gl_impl.cc",
+    "child_gl_impl.h",
+  ]
+}
+
 source_set("util") {
   deps = [
     "//cc",