Fix error reported by ASAN in 139.asan.0.581.pdf

==15244== ERROR: AddressSanitizer: SEGV on unknown address 0x605df000f3ee (pc 0x7f1087b3a22e sp 0x7fffec30ff20 bp 0x7fffec30ff80 T0)
AddressSanitizer can not provide additional info.
    #0 0x7f1087b3a22d (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x48f22d)
    #1 0x7f1087b19d92 (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x46ed92)
    #2 0x7f1087ae570b (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x43a70b)
    #3 0x7f1087ae4061 (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x439061)
    #4 0x7f1087ab9b38 (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x40eb38)
    #5 0x7f1087900989 (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x255989)
    #6 0x7f10878f733a (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x24c33a)
    #7 0x7f10878f650f (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x24b50f)
    #8 0x7f10878f6163 (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x24b163)
    #9 0x7f10879d8dd1 (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x32ddd1)
    #10 0x7f10879e02fd (/home/tsdgeos/devel/poppler/build-debug/libpoppler.so.46.0.0+0x3352fd)
    #11 0x40311e (/home/tsdgeos/devel/poppler/build-debug/utils/pdftoppm+0x40311e)
    #12 0x404416 (/home/tsdgeos/devel/poppler/build-debug/utils/pdftoppm+0x404416)
    #13 0x7f1087000ec4 (/lib/x86_64-linux-gnu/libc-2.19.so+0x21ec4)
    #14 0x401d58 (/home/tsdgeos/devel/poppler/build-debug/utils/pdftoppm+0x401d58)
Fix error reported by ASAN in 2010.asan.0.1506.pdf

==18859== ERROR: AddressSanitizer: unknown-crash on address 0x7f1e4a6beb50 at pc 0x7f1e5557444d bp 0x7fff6af3c340 sp 0x7fff6af3bb00
WRITE of size 442216446 at 0x7f1e4a6beb50 thread T0
    #0 0x7f1e5557444c (/usr/lib/x86_64-linux-gnu/libasan.so.0+0xe44c)
    #1 0x7f1e550e04ff in SplashFont::getGlyph(int, int, int, SplashGlyphBitmap*, int, int, SplashClip*, SplashClipResult*) /home/tsdgeos/devel/poppler/splash/SplashFont.cc:206
    #2 0x7f1e550d9c69 in SplashFTFont::getGlyph(int, int, int, SplashGlyphBitmap*, int, int, SplashClip*, SplashClipResult*) /home/tsdgeos/devel/poppler/splash/SplashFTFont.cc:233
    #3 0x7f1e550a5368 in Splash::fillChar(double, double, int, SplashFont*) /home/tsdgeos/devel/poppler/splash/Splash.cc:2714
    #4 0x7f1e55078a20 in SplashOutputDev::drawChar(GfxState*, double, double, double, double, double, double, unsigned int, int, unsigned int*, int) /home/tsdgeos/devel/poppler/poppler/SplashOutputDev.cc:2270
    #5 0x7f1e54ed9599 in Gfx::doShowText(GooString*) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:4054
    #6 0x7f1e54ed6db0 in Gfx::opShowSpaceText(Object*, int) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:3886
    #7 0x7f1e54eb533a in Gfx::execOp(Object*, Object*, int) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:903
    #8 0x7f1e54eb450f in Gfx::go(bool) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:762
    #9 0x7f1e54eb4163 in Gfx::display(Object*, bool) /home/tsdgeos/devel/poppler/poppler/Gfx.cc:728
    #10 0x7f1e54f96dd1 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:585
    #11 0x7f1e54f9e2fd 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:503
    #12 0x40311e in savePageSlice(PDFDoc*, SplashOutputDev*, int, int, int, int, int, double, double, char*) /home/tsdgeos/devel/poppler/utils/pdftoppm.cc:222
    #13 0x404416 in main /home/tsdgeos/devel/poppler/utils/pdftoppm.cc:521
    #14 0x7f1e545beec4 (/lib/x86_64-linux-gnu/libc.so.6+0x21ec4)
    #15 0x401d58 in _start (/home/tsdgeos/devel/poppler/build-debug/utils/pdftoppm+0x401d58)