In looking at the code coverage on oss-fuzz, I realized the encoding
support never goes down paths related to options being not the default,
so go ahead and allow the existing options extraction to set those also,
so we're running everything possible to help look for bugs.
All but one of the options defaulted to "false", so since the fuzz
options parsing was ensuring the extra bits were zero, it is safe to
just add the option. The one that wasn't zero, we add a new "inverted"
bool so all saved cases remain valid.
This also gave us the change to control "partial" on binary decoding, so
wire that up also.
Lastly, while at it, increase the options logging so it is a little more
complete.
In Binary, TextFormat, and JSON, a leading byte is not value, so leverage that
to indicate that the next byte should be used as bits for decoding options.
Make the proto namespace used more consistent and ensure they are scoped to this
project more clearly.
Delete files that don't seem to be use/validating anything.
On macOS this requires using a swift.org toolchain since the swift support in
Xcode doesn't include fuzz support.
Add a second stage to the 'build' CI workflow to ensure these targets stay
building also.
Thomas Van Lenten
Gus Cairo