Another uniscribe crash

[ebraminio]

Apparently the fix on b17e1a4 wasn't enough

Ebrahim@DESKTOP MINGW64 ~/harfbuzz
$ util/hb-shape /c/Windows/Fonts/himalaya.ttf -u '0f21 0f3f' --shapers directwrite
[gid310=0+680|gid279=1+655]

Ebrahim@DESKTOP MINGW64 ~/harfbuzz
$ util/hb-shape /c/Windows/Fonts/himalaya.ttf -u '0f21 0f3f' --shapers uniscribe
Segmentation fault

Ebrahim@DESKTOP MINGW64 ~/harfbuzz
$ util/hb-shape /c/Windows/Fonts/himalaya.ttf -u '0f21 0f3f' --shapers ot
[gid279=0+655|gid310=0+680]

Starting program: /home/Ebrahim/harfbuzz/util/.libs/hb-shape.exe himalaya.ttf -u "0f21 0f3f" --shaper=uniscribe
[New Thread 11504.0x27dc]
[New Thread 11504.0xecc]
[New Thread 11504.0xe60]
[New Thread 11504.0x2e0c]

Thread 1 received signal SIGSEGV, Segmentation fault.
OT::CheckSum::CalcTableChecksum (Length=610224, Table=0xf2b004)
    at hb-open-type-private.hh:773
773           Sum += *Table++;

[behdad]

Sorry about that. Should be fixed. My wine is not working so cannot test. Please test.