Running https://bugs.kde.org/attachment.cgi?id=20680 with an asan compiled poppler

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==11234==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x564a56f2fb71 in operator new(unsigned long) (/home/tsdgeos/devel/poppler/build-asan-ubsan/qt5/tests/test-render-to-file-qt5+0x14bb71)
    #1 0x7fd9304fcfb9 in ArthurOutputDev::beginTransparencyGroup(GfxState*, double const*, GfxColorSpace*, bool, bool, bool) /home/tsdgeos/devel/poppler/qt5/src/ArthurOutputDev.cc:1190:20
    #2 0x7fd92ebd5537 in Gfx::drawForm(Object*, Dict*, double const*, double const*, bool, bool, GfxColorSpace*, bool, bool, bool, Function*, GfxColor*) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:4828:10
    #3 0x7fd92ebd4062 in Gfx::doSoftMask(Object*, bool, GfxColorSpace*, bool, bool, Function*, GfxColor*) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:1357:3
    #4 0x7fd92ebc33a6 in Gfx::opSetExtGState(Object*, int) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:1226:4
    #5 0x7fd92ebd2de8 in Gfx::execOp(Object*, Object*, int) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:876:3
    #6 0x7fd92ebd1b15 in Gfx::go(bool) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:752:7
    #7 0x7fd92ebd1289 in Gfx::display(Object*, bool) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:714:3
    #8 0x7fd92ee0112a in Page::displaySlice(OutputDev*, double, double, int, bool, bool, int, int, int, int, bool, bool (*)(void*), void*, bool (*)(Annot*, void*), void*, bool) /home/tsdgeos/devel/poppler/poppler/Page.cc:548:10
    #9 0x7fd92ee145a5 in PDFDoc::displayPageSlice(OutputDev*, int, double, double, int, bool, bool, bool, int, int, int, int, bool (*)(void*), void*, bool (*)(Annot*, void*), void*, bool) /home/tsdgeos/devel/poppler/poppler/PDFDoc.cc:664:20
    #10 0x7fd9304af03b in Poppler::renderToArthur(Poppler::QImageDumpingArthurOutputDev*, QPainter*, Poppler::PageData*, double, double, int, int, int, int, Poppler::Page::Rotation, QFlags<Poppler::Page::PainterFlag>) /home/tsdgeos/devel/poppler/qt5/src/poppler-page.cc:491:25
    #11 0x7fd9304ad8c6 in Poppler::Page::renderToImage(double, double, int, int, int, int, Poppler::Page::Rotation, void (*)(QImage const&, QVariant const&), bool (*)(QVariant const&), bool (*)(QVariant const&), QVariant const&) const /home/tsdgeos/devel/poppler/qt5/src/poppler-page.cc:622:7
    #12 0x7fd9304ac351 in Poppler::Page::renderToImage(double, double, int, int, int, int, Poppler::Page::Rotation, void (*)(QImage const&, QVariant const&), bool (*)(QVariant const&), QVariant const&) const /home/tsdgeos/devel/poppler/qt5/src/poppler-page.cc:519:10
    #13 0x7fd9304ac1c7 in Poppler::Page::renderToImage(double, double, int, int, int, int, Poppler::Page::Rotation) const /home/tsdgeos/devel/poppler/qt5/src/poppler-page.cc:514:10