I have a jar which contains a web-fragment and no TLDs. When starting the server I get the Message: org.apache.jasper.compiler.TldLocationsCache tldScanJar INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time. so far so good. When adding it to the tomcat.util.scan.DefaultJarScanner.jarsToSkip property the web-fragment won't be scanned either. The log message should only be printed when no TLDs and web-fragments could be found in the jar.
Fixed in trunk and 7.0.x and will be included in 7.0.30 onwards. Note the fix was implemented using additional system properties. Determining if a JAR had contributed to a Servlet 3.0 pluggability feature and then passing that info the the TLD scanner would have been a much more invasive patch.