GN: Fix NaCl IRT build options

build/toolchain/nacl/BUILD.gn

 # Copyright (c) 2014 The Native Client 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/sysroot.gni")
 import("//build/config/nacl/config.gni")
 import("//build/toolchain/nacl_toolchain.gni")
 
 # Add the toolchain revision as a preprocessor define so that sources are
 # rebuilt when a toolchain is updated.
@@ skipping 103 matching lines @@
                   root_build_dir)
   tls_edit = "${host_toolchain_out_dir}/tls_edit"
 
   nacl_toolchain("irt_" + toolchain_cpu) {
     is_clang = true
     cc = toolprefix + "clang"
     cxx = toolprefix + "clang++"
     ar = toolprefix + "ar"
     readelf = toolprefix + "readelf"
 
+    # Always build the IRT with full debugging symbols, regardless of
+    # how Chromium itself is being built (or other NaCl executables).
+    symbol_level = 2
+
     # Some IRT implementations (notably, Chromium's) contain C++ code,
     # so we need to link w/ the C++ linker.
     ld = "${python_path} ${link_irt} --tls-edit=${tls_edit} --link-cmd=${cxx} --readelf-cmd=${readelf}"
 
     # TODO(ncbray): depend on link script
     deps = [
       tls_edit_label,
     ]
   }
 }
@@ skipping 12 matching lines @@
   toolchain_tuple = "i686-nacl"
 }
 
 nacl_clang_toolchains("x64") {
   toolchain_tuple = "x86_64-nacl"
 }
 
 nacl_clang_toolchains("arm") {
   toolchain_tuple = "arm-nacl"
 }