Un-nest configs in GN files.

third_party/libxslt/BUILD.gn

Index: third_party/libxslt/BUILD.gn
diff --git a/third_party/libxslt/BUILD.gn b/third_party/libxslt/BUILD.gn
index 6b46db384f56dda1354718f69fa56b5b74767a87..1ecb11cf2e2aeee4bcc6f27047788a2c777209e1 100644
--- a/third_party/libxslt/BUILD.gn
+++ b/third_party/libxslt/BUILD.gn
@@ -7,6 +7,19 @@ config("libxslt_config") {
   include_dirs = [ "." ]
 }
 
+config("libxslt_warnings") {
+  if (is_clang) {
+    cflags = [
+      # libxslt stores a char[3] in a `const unsigned char*`.
+      "-Wno-pointer-sign",
+
+      # xsltDefaultRegion and xsltCalibrateTimestamps are only
+      # used with certain preprocessor defines set.
+      "-Wno-unused-function",
+    ]
+  }
+}
+
 static_library("libxslt") {
   sources = [
     "libxslt/attributes.c",
@@ -59,21 +72,11 @@ static_library("libxslt") {
     "win32/config.h",
   ]
 
-  config("libxslt_warnings") {
-    if (is_clang) {
-      cflags = [
-        # libxslt stores a char[3] in a `const unsigned char*`.
-        "-Wno-pointer-sign",
-
-        # xsltDefaultRegion and xsltCalibrateTimestamps are only
-        # used with certain preprocessor defines set.
-        "-Wno-unused-function",
-      ]
-    }
-  }
   configs -= [ "//build/config/compiler:chromium_code" ]
-  configs += [ "//build/config/compiler:no_chromium_code" ]
-  configs += [ ":libxslt_warnings" ]
+  configs += [
+    ":libxslt_warnings",
+    "//build/config/compiler:no_chromium_code",
+  ]
   public_configs = [ ":libxslt_config" ]
 
   cflags = []