OpenSystemsDevelopment / qpdf

If duplicate keys are encountered, overwrite earlier values with the latest
value.

Except for virtual functions to avoid the need for users to update code.

Also, move Buffer::Members definition to Buffer.cc

Fix the logic to accept a top-level `zopfli.h` header, as that is
the location used by upstream's build system.

Removing it was ABI-breaking. I must have done it forgetting Pl_DCT.hh
was in the public API.

This improves indentation of long strings. This commit also fixes some
trailing whitespace in ChangeLog.

Reduce the container size for which a single bad token will cause a failure
from 100,000 to 5,000.

Count missing dictionary keys as errors.

If a flate memory limit is set, reject decode parameters that would cause
the limit to be exceeded and treat stream as unfilterable.

Fixes oss-fuzz issue 394463491

The stream filter is only used if the stream is filterable, therefore
there is no point continuing to set decode parameters once it is recognized
that the stream is not filterable.

Fail if a bad token is encountered while parsing an array or dictionary
with more than 100,000 elements.

Fixes oss-fuzz case 388571629.

Fixes oss-fuzz case 394129398.

Issue arose from chaining multiple runlength filters and inflating a
compressed stream of ~100 bytes to several gigabytes.

There is no obvious fix without imposing an arbitrary implementation limit
and therefore potentially excluding valid PDF files.

This requires a special build option.

Check for direct outline items.

Fixes oss-fuzz case 	389339260.

Fixes oss-fuzz cases 376305073, 389974979 and 391974927.

When recovering XRef streams, start with the stream with the largest
/Size rather than the largest offset.

Also, if reconstruction fails to find a trailer with a valid /Root entry
search for a root object.

Change QPDFWriter stream_decode_level default to qpdf_dl_generalized (fixes #1286)

runtime error

Also, fix disabling of preserve_encryption to be ignore
stream_decode_level, but disable preserve_encryption if compress_streams is
false.

Fixes #1286

without filtering

Use NAMES keyword in find_library call

Fix QPDF::getAllPagesInternal warning

Fix QPDF::copyForeignObject warning

Provide correct obj_gen and offset.

Provide correct obj_gen.

This reverts commit ff2a78f579ebdd06b417e34260a17dba06e71137, reversing
changes made to 8f54319f7a6514110f4b05cbbf1cb1c9fc8cb6a0.