Get a descriptive error name from ICU

net/base/net_util_icu.cc

 // Copyright (c) 2012 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.
 
 #include "net/base/net_util.h"
 
 #include <map>
 #include <vector>
 
 #include "base/i18n/time_formatting.h"
 #include "base/json/string_escape.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/memory/singleton.h"
 #include "base/stl_util.h"
 #include "base/strings/string_tokenizer.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_offset_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
 #include "url/gurl.h"
 #include "third_party/icu/source/common/unicode/uidna.h"
 #include "third_party/icu/source/common/unicode/uniset.h"
 #include "third_party/icu/source/common/unicode/uscript.h"
 #include "third_party/icu/source/common/unicode/uset.h"
+#include "third_party/icu/source/common/unicode/utypes.h"
 #include "third_party/icu/source/i18n/unicode/datefmt.h"
 #include "third_party/icu/source/i18n/unicode/regex.h"
 #include "third_party/icu/source/i18n/unicode/ulocdata.h"
 
 using base::Time;
 
 namespace net {
 
 namespace {
 
@@ skipping 255 matching lines @@
 // It also closely matches what IE 10 does except for the BiDi check (
 // http://goo.gl/3XBhqw ).
 // See http://http://unicode.org/reports/tr46/ and references therein
 // for more details.
 struct UIDNAWrapper {
   UIDNAWrapper() {
     UErrorCode err = U_ZERO_ERROR;
     // TODO(jungshik): Change options as different parties (browsers,
     // registrars, search engines) converge toward a consensus.
     value = uidna_openUTS46(UIDNA_CHECK_BIDI, &err);
-    if (U_FAILURE(err))
+    if (U_FAILURE(err)) {
+      CHECK(false) << "failed to open UTS46 data with error: "
+                   << u_errorName(err);
       value = NULL;
+    }
   }
 
   UIDNA* value;
 };
 
 static base::LazyInstance<UIDNAWrapper>::Leaky
     g_uidna = LAZY_INSTANCE_INITIALIZER;
 
 // Converts one component of a host (between dots) to IDN if safe. The result
 // will be APPENDED to the given output string and will be the same as the input
@@ skipping 517 matching lines @@
   if (offset_for_adjustment)
     offsets.push_back(*offset_for_adjustment);
   base::string16 result = FormatUrlWithOffsets(url, languages, format_types,
       unescape_rules, new_parsed, prefix_end, &offsets);
   if (offset_for_adjustment)
     *offset_for_adjustment = offsets[0];
   return result;
 }
 
 }  // namespace net