Move libc++ configs and flags out of //build/config/sanitizers

extensions/shell/installer/linux/BUILD.gn

 # Copyright 2017 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.
 
 # TODO(michaelpg): Dedupe with Chrome installer.
 
+import("//build/config/c++/c++.gni")
 import("//build/config/chrome_build.gni")
 import("//build/config/features.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/sysroot.gni")
 import("//build/util/version.gni")
 import("//chrome/process_version_rc_template.gni")  # For branding_file_path.
 import("//extensions/features/features.gni")
 
 assert(is_desktop_linux)
 assert(current_cpu == "x64")
@@ skipping 103 matching lines @@
   if (enable_nacl) {
     public_deps += [
       "//components/nacl/loader:nacl_helper",
 
       # These are data_deps of nacl_helper, but that is not enough,
       # as explained above.
       "//native_client/src/trusted/service_runtime/linux:bootstrap",
       "//ppapi/native_client:irt",
     ]
   }
-  if (use_custom_libcxx) {
-    public_deps += [ "//buildtools/third_party/libc++" ]
-  }
 }
 
 # Creates .deb installer package.
 #
 # channel:
 #   Name of the channel.
 template("linux_package") {
   testonly = true
   assert(defined(invoker.channel))
   channel = invoker.channel
 
   packaging_files_binaries = [
     # TODO(mmoss) Any convenient way to get all the relevant build
     # files? (e.g. all locales, resources, etc.)
     "$root_out_dir/app_shell",
     "$root_out_dir/extensions_shell_and_test.pak",
   ]
 
   if (enable_nacl) {
     packaging_files_binaries += [
       "$root_out_dir/nacl_helper",
       "$root_out_dir/nacl_helper_bootstrap",
       "$root_out_dir/nacl_irt_x86_64.nexe",
     ]
   }
 
-  if (use_custom_libcxx) {
+  # TODO(thomasanderson): Move this variable into a .gni file
+  # somewhere.  It is currently copied from
+  # buildtools/third_party/libc++/BUILD.gn.
+  libcpp_is_static = !is_component_build && !using_sanitizer
+  if (!libcpp_is_static && use_custom_libcxx) {
     packaging_files_binaries += [ "$root_out_dir/libc++.so" ]
   }
 
   deb_target_name = "${target_name}_deb"
   action(deb_target_name) {
     visibility = [ ":*" ]
     script = "//chrome/installer/linux/flock_make_package.py"
     deb_arch = "amd64"
 
     inputs = packaging_files_binaries
@@ skipping 44 matching lines @@
 # Other packages that we support that aren't included in the default "linux"
 # target.
 linux_package("trunk") {
   channel = "trunk"
 }
 if (is_asan) {
   linux_package("asan") {
     channel = "asan"
   }
 }