Upgrade Antlr to 4.7.1 and get rid of bug workaround

CHANGELOG

@@ -185,3 +185,7 @@ v3.3
 - By default do not load all test cases into memory
 - Fixed NPE in parse error situation (Hacker scenario)
 - Never let any NPE disturb the calling application ever again
+
+v3.4
+===
+- Upgrade Antlr to 4.7.1 and get rid of bug workaround

analyzer/pom.xml

@@ -34,7 +34,7 @@
   <url>http://github.com/nielsbasjes/yauaa</url>
 
   <properties>
-    <antlr.version>4.7</antlr.version>
+    <antlr.version>4.7.1</antlr.version>
   </properties>
 
   <dependencies>

analyzer/src/main/java/nl/basjes/parse/useragent/parse/UserAgentTreeFlattener.java

@@ -54,7 +54,6 @@
 import nl.basjes.parse.useragent.utils.Splitter;
 import nl.basjes.parse.useragent.utils.VersionSplitter;
 import nl.basjes.parse.useragent.utils.WordSplitter;
-import org.antlr.v4.runtime.CharStream;
 import org.antlr.v4.runtime.CharStreams;
 import org.antlr.v4.runtime.CodePointCharStream;
 import org.antlr.v4.runtime.CommonTokenStream;
@@ -262,14 +261,7 @@ private UserAgentContext parseUserAgent(UserAgent userAgent) {
     @Override
     public void enterUserAgent(UserAgentContext ctx) {
         // In case of a parse error the 'parsed' version of agent can be incomplete
-        // TODO: Remove this workaround for the Antlr 4.7 bug described here https://github.com/antlr/antlr4/issues/1949
-//        String input = ctx.start.getTokenSource().getInputStream().toString();
-        String input = "";
-        CharStream inputCharStream = ctx.start.getTokenSource().getInputStream();
-        if (inputCharStream.size() > 0) {
-            input = inputCharStream.toString();
-        }
-        inform(ctx, "agent", input);
+        inform(ctx, "agent", ctx.start.getTokenSource().getInputStream().toString());
     }
 
     @Override