Update ICU to 58.1

source/common/ucase.cpp

Index: source/common/ucase.cpp
diff --git a/source/common/ucase.cpp b/source/common/ucase.cpp
index b04c2d40cf0c45a1d669eda6c7ca8c1cd3f5fde1..97ded9ee2d15f6750664517cc96ca73d2c18dc55 100644
--- a/source/common/ucase.cpp
+++ b/source/common/ucase.cpp
@@ -1,3 +1,5 @@
+// Copyright (C) 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
 /*
 *******************************************************************************
 *
@@ -619,6 +621,18 @@ ucase_getCaseLocale(const char *locale, int32_t *locCache) {
                 result=UCASE_LOC_LITHUANIAN;
             }
         }
+    } else if(is_e(c)) {
+        /* el or ell? */
+        c=*locale++;
+        if(is_l(c)) {
+            c=*locale++;
+            if(is_l(c)) {
+                c=*locale;
+            }
+            if(is_sep(c)) {
+                result=UCASE_LOC_GREEK;
+            }
+        }
     } else if(is_n(c)) {
         /* nl or nld? */
         c=*locale++;
@@ -801,8 +815,9 @@ U_CAPI int32_t U_EXPORT2
 ucase_toFullLower(const UCaseProps *csp, UChar32 c,
                   UCaseContextIterator *iter, void *context,
                   const UChar **pString,
-                  const char *locale, int32_t *locCache)
-{
+                  const char *locale, int32_t *locCache) {
+    // The sign of the result has meaning, input must be non-negative so that it can be returned as is.
+    U_ASSERT(c >= 0);
     UChar32 result=c;
     uint16_t props=UTRIE2_GET16(&csp->trie, c);
     if(!PROPS_HAS_EXCEPTION(props)) {
@@ -947,6 +962,8 @@ toUpperOrTitle(const UCaseProps *csp, UChar32 c,
                const UChar **pString,
                const char *locale, int32_t *locCache,
                UBool upperNotTitle) {
+    // The sign of the result has meaning, input must be non-negative so that it can be returned as is.
+    U_ASSERT(c >= 0);
     UChar32 result=c;
     uint16_t props=UTRIE2_GET16(&csp->trie, c);
     if(!PROPS_HAS_EXCEPTION(props)) {
@@ -1155,8 +1172,9 @@ ucase_fold(const UCaseProps *csp, UChar32 c, uint32_t options) {
 U_CAPI int32_t U_EXPORT2
 ucase_toFullFolding(const UCaseProps *csp, UChar32 c,
                     const UChar **pString,
-                    uint32_t options)
-{
+                    uint32_t options) {
+    // The sign of the result has meaning, input must be non-negative so that it can be returned as is.
+    U_ASSERT(c >= 0);
     UChar32 result=c;
     uint16_t props=UTRIE2_GET16(&csp->trie, c);
     if(!PROPS_HAS_EXCEPTION(props)) {