Meta: Support GPU painting in the GN build

Meta/gn/secondary/Ladybird/BUILD.gn

@@ -211,6 +211,7 @@ if (current_os == "mac") {
 
   bundle_data("ladybird_bundle_libs") {
     public_deps = [
+      "//Userland/Libraries/LibAccelGfx",
       "//Userland/Libraries/LibAudio",
       "//Userland/Libraries/LibCompress",
       "//Userland/Libraries/LibCore",
@@ -247,6 +248,7 @@ if (current_os == "mac") {
       "//Userland/Libraries/LibXML",
     ]
     sources = [
+      "$root_out_dir/lib/liblagom-accelgfx.dylib",
       "$root_out_dir/lib/liblagom-audio.dylib",
       "$root_out_dir/lib/liblagom-compress.dylib",
       "$root_out_dir/lib/liblagom-core.dylib",

Meta/gn/secondary/Ladybird/WebContent/BUILD.gn

@@ -70,4 +70,8 @@ executable("WebContent") {
     "main.cpp",
   ]
   sources += get_target_outputs(":generate_moc")
+
+  if (current_os == "linux" || current_os == "mac") {
+    cflags_cc = [ "-DHAS_ACCELERATED_GRAPHICS" ]
+  }
 }

Meta/gn/secondary/Userland/Libraries/LibAccelGfx/BUILD.gn

@@ -7,12 +7,16 @@ shared_library("LibAccelGfx") {
     "//Userland/Libraries/LibCore",
     "//Userland/Libraries/LibGfx",
   ]
+
   if (current_os == "linux") {
     libs = [
       "GL",
       "EGL",
     ]
+  } else if (current_os == "mac") {
+    frameworks = [ "OpenGL.framework" ]
   }
+
   sources = [
     "Canvas.h",
     "Context.cpp",

Meta/gn/secondary/Userland/Libraries/LibWeb/Painting/BUILD.gn

@@ -40,7 +40,8 @@ source_set("Painting") {
     "VideoPaintable.cpp",
     "ViewportPaintable.cpp",
   ]
-  if (current_os == "linux") {
+
+  if (current_os == "linux" || current_os == "mac") {
     sources += [ "PaintingCommandExecutorGPU.cpp" ]
     public_deps = [ "//Userland/Libraries/LibAccelGfx" ]
   }