2 test cases of JCK api/java_net/URLConnection/descriptions.html#getHeaderField test fails starting from jdk8 b19.
These testcases are new in JCK8 and verify that 
getHeaderFields() Returns an unmodifiable Map of the header fields.. and 
Each Map value is an unmodifiable List of Strings that represents the corresponding field values..

Test cases fails with message like:
java version "1.8.0-ea"
Java(TM) SE Runtime Environment (build 1.8.0-ea-b19)
Java HotSpot(TM) Server VM (build 23.0-b09, mixed mode)

getHeaderFields02: Failed. getHeaderFields() returned modifiable Map
java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextEntry(HashMap.java:839)
        at java.util.HashMap$ValueIterator.next(HashMap.java:868)
        at javasoft.sqe.tests.api.java.net.URLConnection.getHeaderFieldTests.getHeaderFields03(getHeaderFieldTests.java:4044)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:474)
        at javasoft.sqe.javatest.lib.MultiTest.invokeTestCase(MultiTest.java:405)
        at javasoft.sqe.tests.api.java.net.URLConnection.getHeaderFieldTests.invokeTestCase(getHeaderFieldTests.java:106)
        at javasoft.sqe.javatest.lib.MultiTest.run(MultiTest.java:194)
        at javasoft.sqe.javatest.lib.MultiTest.run(MultiTest.java:126)
        at javasoft.sqe.tests.api.java.net.URLConnection.getHeaderFieldTests.main(getHeaderFieldTests.java:138)
getHeaderFields03: Failed. Test case throws exception: java.util.ConcurrentModificationException
Collection changed after clear()
Initial collection: {null=[HTTP/1.1 200 OK], ETag=["1f598ddd-1ace-c9e704c0"], Date=[Tue, 28 Feb 2012 10:57:02 GMT], Content-Length=[6862], Last-Modified=[Thu, 05 Aug 2010 17:22:03 GMT], Keep-Alive=[timeout=15, max=100], Accept-Ranges=[bytes], Connection=[Keep-Alive], Content-Type=[text/plain], Server=[Apache/2.0.63 (Unix) DAV/2]}
Changed collection: {}
STATUS:Failed.test cases: 2; all failed; first test case failure: getHeaderFields02

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