[Testbug] tools/launcher tests need to tolerate unrelated warnings

Discovered during JDK 11 version update testing when VM obsoletion warnings are enabled.

tools/launcher/InfoStreams.java
tools/launcher/ToolsOpts.java

 stderr: [Java HotSpot(TM) 64-Bit Server VM warning: Global variable for obsolete special flag entry "FastTLABRefill" should be removed
Java HotSpot(TM) 64-Bit Server VM warning: Global variable for obsolete special flag entry "SafepointSpinBeforeYield" should be removed
Java HotSpot(TM) 64-Bit Server VM warning: Global variable for obsolete special flag entry "DeferThrSuspendLoopCount" should be removed
Java HotSpot(TM) 64-Bit Server VM warning: Global variable for obsolete special flag entry "DeferPollingPageLoopCount" should be removed
Java HotSpot(TM) 64-Bit Server VM warning: Global variable for expired flag entry "UseCGroupMemoryLimitForHeap" should be removed
]
 exitValue = 0

java.lang.RuntimeException: '.' found in stderr

at jdk.testlibrary.OutputAnalyzer.stderrShouldNotMatch(OutputAnalyzer.java:322)
at InfoStreams.main(InfoStreams.java:56)




----------System.err:(14/1080)----------
java.lang.RuntimeException: failed! CMD: /scratch/opt/mach5/mesos/work_dir/jib-master/install/2018-02-01-2235488.david.holmes.jdk-master/linux-x64-debug.jdk/jdk-11/fastdebug/bin/javac -J--patch-module=jdk.compiler=jdk.compiler -option
   case:Java HotSpot(TM) 64-Bit Server VM warning: Global variable for obsolete special flag entry "FastTLABRefill" should be removed != -option
at ToolsOpts.runTestOptions(ToolsOpts.java:200)
at ToolsOpts.main(ToolsOpts.java:213)