Shrink gn's chrome.dll - now smaller than gyp's

gpu/command_buffer/service/BUILD.gn

Index: gpu/command_buffer/service/BUILD.gn
diff --git a/gpu/command_buffer/service/BUILD.gn b/gpu/command_buffer/service/BUILD.gn
index 14f25b66b7049e99d163c469e029536a715ec82e..7858b575de147517199fc80ae6bb3c3eb057e975 100644
--- a/gpu/command_buffer/service/BUILD.gn
+++ b/gpu/command_buffer/service/BUILD.gn
@@ -17,7 +17,12 @@ group("service") {
   }
 }
 
-source_set("service_sources") {
+if (is_component_build) {
+  link_target_type = "source_set"
+} else {
+  link_target_type = "static_library"
+}
+target(link_target_type, "service_sources") {
   # External code should depend on this via //gpu/command_buffer/service above
   # rather than depending on this directly or the component build will break.
   visibility = [ "//gpu/*" ]