[8u60] Request for Review: 8094649: [Mac] Intermittent crash after starting Multitouch support

[Morris Meyer]

Kevin and David,

Please review the following one-line fix to 8094649.  This issue was 
caused by a race condition between start of touch tracking and the 
closing out the splash screen without removing the touch tracking. It 
was messaging the invalid ObjC object for the GlassViewDelegate and 
crashing.

This has been tested using HelloSanity and using the test app linked in 
this issue.

         --morris

WEBREV - http://cr.openjdk.java.net/~morris/JDK-8094649.01/
JBS - https://bugs.openjdk.java.net/browse/JDK-8094649