Update ICU to 58.1

source/i18n/collationfastlatinbuilder.cpp

Index: source/i18n/collationfastlatinbuilder.cpp
diff --git a/source/i18n/collationfastlatinbuilder.cpp b/source/i18n/collationfastlatinbuilder.cpp
index d5acda15b0175597ade7db6c2d0737ab5f5c6e94..032e5e82aaef1508e13382b91efb22a83231dbe1 100644
--- a/source/i18n/collationfastlatinbuilder.cpp
+++ b/source/i18n/collationfastlatinbuilder.cpp
@@ -1,3 +1,5 @@
+// Copyright (C) 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
 /*
 *******************************************************************************
 * Copyright (C) 2013-2015, International Business Machines
@@ -147,7 +149,7 @@ CollationFastLatinBuilder::loadGroups(const CollationData &data, UErrorCode &err
             // missing data
             return FALSE;
         }
-        result.append(0);  // reserve a slot for this group
+        result.append((UChar)0);  // reserve a slot for this group
     }
 
     firstDigitPrimary = data.getFirstPrimaryForGroup(UCOL_REORDER_CODE_DIGIT);
@@ -564,7 +566,7 @@ CollationFastLatinBuilder::encodeCharCEs(UErrorCode &errorCode) {
     if(U_FAILURE(errorCode)) { return FALSE; }
     int32_t miniCEsStart = result.length();
     for(int32_t i = 0; i < CollationFastLatin::NUM_FAST_CHARS; ++i) {
-        result.append(0);  // initialize to completely ignorable
+        result.append((UChar)0);  // initialize to completely ignorable
     }
     int32_t indexBase = result.length();
     for(int32_t i = 0; i < CollationFastLatin::NUM_FAST_CHARS; ++i) {