[8u20] Request for approval: 8017456 - [TEST_BUG] java/awt/DataFlavor/MissedHtmlAndRtfBug/MissedHtmlAndRtfBug.html: test frames remain after test execution

[Konstantin Shefov]

Please approve the simple backport from jdk9.

Bug: https://bugs.openjdk.java.net/browse/JDK-8017456
Fix pushed as: http://hg.openjdk.java.net/jdk9/client/jdk/rev/9c9d4a85a248
Fix applies without an issue to 
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/jdk
Webrev is available at: 
http://cr.openjdk.java.net/~kshefov/8017456/webrev.00

/Konstantin