tst_controls::Tumbler::test_displacementListView() fails on Red Hat 4.9.1-10

********* Start testing of tst_controls *********
 Config: Using QtTest library 5.6.2, Qt 5.6.2 (x86_64-little_endian-lp64 shared (dynamic) release build; by GCC 4.9.1 20140922 (Red Hat 4.9.1-10))
 PASS   : tst_controls::Tumbler::initTestCase()
 PASS   : tst_controls::Tumbler::test_displacementListView(contentY=-66.66666666666667)
 FAIL!  : tst_controls::Tumbler::test_displacementListView(contentY=-50) Delegate of ListView-based Tumbler at index 0 has displacement of 1.2449999999999999 when it should be 0.25
    Actual   (): 1.2449999999999999
    Expected (): 0.25
    Loc: [/home/qt/work/qt/qtquickcontrols2/tests/auto/controls/data/tst_tumbler.qml(408)]
 PASS   : tst_controls::Tumbler::test_displacementListView(contentY=-33.333333333333336)
 FAIL!  : tst_controls::Tumbler::test_displacementListView(contentY=-16.66666666666667) Delegate of ListView-based Tumbler at index 0 has displacement of 1.8749999999999998 when it should be 0.75
    Actual   (): 1.8749999999999998
    Expected (): 0.75
    Loc: [/home/qt/work/qt/qtquickcontrols2/tests/auto/controls/data/tst_tumbler.qml(408)]
 PASS   : tst_controls::Tumbler::test_displacementListView(contentY=166.66666666666669)
 PASS   : tst_controls::Tumbler::cleanupTestCase()
 Totals: 5 passed, 2 failed, 0 skipped, 0 blacklisted
 ********* Finished testing of tst_controls *********