Un-nest configs in GN files.

third_party/harfbuzz-ng/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/chrome_build.gni")
 import("//build/config/linux/pkg_config.gni")
 import("//build/config/ui.gni")
 
 # The GYP build supports system harfbuzz for non-official builds when using
 # pangoft2 1.31.0 or greater (which pulls it in).
@@ skipping 23 matching lines @@
     packages = [ "harfbuzz" ]
   }
   group("harfbuzz-ng") {
     public_configs = [ ":harfbuzz_pkgconfig" ]
   }
 } else {
   config("harfbuzz-ng_config") {
     include_dirs = [ "src" ]
   }
 
+  config("harfbuzz_warnings") {
+    cflags = []
+    if (is_clang) {
+      cflags += [
+        "-Wno-unused-value",
+
+        # Harfbuzz uses unused typedefs for its static asserts (and its
+        # static asserts are strange enough that they can't be replaced
+        # by static_assert).
+        "-Wno-unused-local-typedef",
+      ]
+    }
+    if (is_win) {
+      # Result of 32-bit shift implicitly converted to 64 bits.
+      cflags += [ "/wd4334" ]
+    }
+  }
+
+  # See also chrome/browser/ui/libgtk2ui/BUILD.gn which pulls this.
+  config("pangoft2_link_hack") {
+    if (is_linux && use_pango && !is_chromeos && !is_official_build &&
+        current_cpu != "arm" && current_cpu != "mipsel" &&
+        !is_component_build) {
+      # These symbols are referenced from libpangoft2, which will be
+      # dynamically linked later.
+      ldflags =
+          [ "-Wl,-uhb_ft_face_create_cached,-uhb_glib_get_unicode_funcs" ]
+    }
+  }
+
   static_library("harfbuzz-ng") {
     sources = [
       "src/hb-atomic-private.hh",
       "src/hb-blob.cc",
       "src/hb-blob.h",
       "src/hb-buffer-deserialize-json.hh",
       "src/hb-buffer-deserialize-text.hh",
       "src/hb-buffer-private.hh",
       "src/hb-buffer-serialize.cc",
       "src/hb-buffer.cc",
@@ skipping 85 matching lines @@
     ]
 
     defines = [
       "HAVE_OT",
       "HAVE_ICU",
       "HAVE_ICU_BUILTIN",
       "HB_NO_MT",
     ]
 
     configs -= [ "//build/config/compiler:chromium_code" ]
-    configs += [ "//build/config/compiler:no_chromium_code" ]
-
-    config("harfbuzz_warnings") {
-      cflags = []
-      if (is_clang) {
-        cflags += [
-          "-Wno-unused-value",
-
-          # Harfbuzz uses unused typedefs for its static asserts (and its
-          # static asserts are strange enough that they can't be replaced
-          # by static_assert).
-          "-Wno-unused-local-typedef",
-        ]
-      }
-      if (is_win) {
-        cflags += [ "/wd4334" ]  # Result of 32-bit shift implicitly converted to 64 bits.
-      }
-    }
-    configs += [ ":harfbuzz_warnings" ]
-
+    configs += [
+      ":harfbuzz_warnings",

[Nico, 2015/09/01 18:27:47]

Not lgtm, this breaks things. ":harfbuzz_warnings" needs to be listed after
no_chromium_code as no_chromium_code effectively adds -Wall. That's why these
compiler flags are in configs and not just in cflags in the first place.

[Dirk Pranke, 2015/09/01 18:38:38]

I'm guessing that if we change this to:

configs -= [ "...chromium_code" ]
configs += [ "...no_chromium_code" ]
configs += [ ":harfbuzz_warnings"]

things should work? 

[Nico, 2015/09/01 18:42:00]

Yes.

(FWIW, the "usually with the assumption that this limits the visibility" from
the CL description isn't true; it just seemed nicer to me to keep the config
closer to its use.)

+      "//build/config/compiler:no_chromium_code",
+    ]
     public_configs = [ ":harfbuzz-ng_config" ]
 
     deps = [
       "//third_party/icu:icuuc",
     ]
 
     if (is_mac) {
       sources += [
         "src/hb-coretext.cc",
         "src/hb-coretext.h",
@@ skipping 13 matching lines @@
         "//build/config/linux:glib",
       ]
       sources += [
         "src/hb-ft.cc",
         "src/hb-ft.h",
         "src/hb-glib.cc",
         "src/hb-glib.h",
       ]
     }
 
-    # See also chrome/browser/ui/libgtk2ui/BUILD.gn which pulls this.
-    config("pangoft2_link_hack") {
-      if (is_linux && use_pango && !is_chromeos && !is_official_build &&
-          current_cpu != "arm" && current_cpu != "mipsel" &&
-          !is_component_build) {
-        # These symbols are referenced from libpangoft2, which will be
-        # dynamically linked later.
-        ldflags =
-            [ "-Wl,-uhb_ft_face_create_cached,-uhb_glib_get_unicode_funcs" ]
-      }
-    }
   }
 }