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

content/gpu/BUILD.gn

Index: content/gpu/BUILD.gn
diff --git a/content/gpu/BUILD.gn b/content/gpu/BUILD.gn
index 5b0f6b69df84c355be8fce0e1c475b779c8b466f..597b4cd51788e6ec23eb6cc1288447236d82ccf0 100644
--- a/content/gpu/BUILD.gn
+++ b/content/gpu/BUILD.gn
@@ -20,7 +20,12 @@ group("gpu") {
   }
 }
 
-source_set("gpu_sources") {
+if (is_component_build) {
+  link_target_type = "source_set"
+} else {
+  link_target_type = "static_library"
+}
+target(link_target_type, "gpu_sources") {
   # This is an internal content API. Code outside of the content "component"
   # (like content/test and content/shell) should depend on ":gpu" above.
   visibility = [ "//content/*" ]