tools: fix iculslocs to support ICU 65.1

The ICU alias table format changed in
https://unicode-org.atlassian.net/browse/ICU-20627

Because of this, iculslocs.cc needs to handle URES_TABLE format
contents in the res_index.txt file.

PR-URL: #29523
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ujjwal Sharma <usharma1998@gmail.com>

tools/icu/iculslocs.cc

@@ -209,7 +209,8 @@ int dumpAllButInstalledLocales(int lev,
     } else {
       printIndent(bf, lev);
       fprintf(bf, "%s", key);
-      switch (ures_getType(t.getAlias())) {
+      const UResType type = ures_getType(t.getAlias());
+      switch (type) {
         case URES_STRING: {
           int32_t len = 0;
           const UChar* s = ures_getString(t.getAlias(), &len, status);
@@ -218,8 +219,16 @@ int dumpAllButInstalledLocales(int lev,
           fwrite(s, len, 1, bf);
           fprintf(bf, "\"}");
         } break;
+        case URES_TABLE: {
+          fprintf(bf, ":table {\n");
+          dumpAllButInstalledLocales(lev+1, &t, bf, status);
+          printIndent(bf, lev);
+          fprintf(bf, "}\n");
+        } break;
         default: {
-          printf("ERROR: unhandled type in dumpAllButInstalledLocales().\n");
+          printf("ERROR: unhandled type %d for key %s "
+                 "in dumpAllButInstalledLocales().\n",
+                 static_cast<int>(type), key);
           return 1;
         } break;
       }