[LANG-1804] Fix CharSet#getInstance returns null instead of EMPTY when

input setStrs is null #1530

Author: garydgregory

src/changes/changes.xml

@@ -80,6 +80,7 @@ The <action> type attribute can be add,update,fix,remove.
     <action issue="LANG-1729" type="fix" dev="ggregory" due-to="Gary Gregory, Andrei Anischevici, Akshat_Agg">NumberUtils.isParsable() returns true for full width Unicode digits for inputs with a decimal point.</action>
     <action issue="LANG-1803" type="fix" dev="ggregory" due-to="IcoreE">Fix incorrect method invocation in ObjectUtilsTest and Javadoc reference in RandomStringUtils.</action>
     <action issue="LANG-1695" type="fix" dev="ggregory" due-to="Guillaume Nodet, Harshit Goel, Gary Gregory">Allow trailing decimal point in NumberUtils.isParsable #1531.</action>
+    <action issue="LANG-1804" type="fix" dev="ggregory" due-to="IcoreE, Gary Gregory">Fix CharSet#getInstance returns null instead of EMPTY when input setStrs is null #1530.</action>
     <!-- ADD -->
     <!-- UPDATE -->
     <action                   type="update" dev="ggregory" due-to="Gary Gregory, Dependabot">Bump org.apache.commons:commons-parent from 92 to 93 #1498.</action>