Set U_NOEXCEPT to empty to avoid C4577 from MSVC

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("//third_party/icu/config.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
 
 # Meta target that includes both icuuc and icui18n. Most targets want both.
 # You can depend on the individually if you need to.
 group("icu") {
   public_deps = [
     ":icui18n",
     ":icuuc",
   ]
 }
 
 # Shared config used by ICU and all dependents.
 config("icu_config") {
   defines = [
     # Tell ICU to not insert |using namespace icu;| into its headers,
     # so that chrome's source explicitly has to use |icu::|.
     "U_USING_ICU_NAMESPACE=0",
 
     # We don't use ICU plugins and dyload is only necessary for them.
     # NaCl-related builds also fail looking for dlfcn.h when it's enabled.
     "U_ENABLE_DYLOAD=0",
+
+    # With exception disabled, MSVC emits C4577 warning on coming across
+    # 'noexcept'. See http://bugs.icu-project.org/trac/ticket/12406
+    # TODO(jshin): Remove this when updating to a newer version with this fixed.
+    "U_NOEXCEPT=",
   ]
 
   if (!is_component_build) {
     defines += [ "U_STATIC_IMPLEMENTATION" ]
   }
 
   include_dirs = [
     "source/common",
     "source/i18n",
   ]
@@ skipping 575 matching lines @@
         sources = [
           "android/icudtl_dat.S",
         ]
       } else {
         assert(false, "No icu data for this platform")
       }
       defines = [ "U_HIDE_DATA_SYMBOL" ]
     }
   }
 }