language-server: fixed missing import after merge

Author: joshtynjala

language-server/src/main/java/com/as3mxml/vscode/ActionScriptTextDocumentService.java

@@ -46,6 +46,7 @@
 
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.io.output.ByteArrayOutputStream;
+import org.apache.royale.abc.ABCConstants;
 import org.apache.royale.compiler.clients.problems.ProblemQuery;
 import org.apache.royale.compiler.common.ASModifier;
 import org.apache.royale.compiler.common.ISourceLocation;