[TEST_BUG] javax/swing/PopupFactory/6276087/NonOpaquePopupMenuTest.java doesn't release mouse button

test passed but doesn't release mouse button, this cause failure of plenty other regression tests - see INTJDK-7118889

test excluded from execution in the regression team suite, it should be removed from notrun.txt after fix this bug for all trains (jdk6-jdk8, there is no such test in jdk5)