mapnik_symbolizer compilation errors on MASON_BUILD=true

[JonPeel]

Trying to follow the docs for the MASON_BUILD approach. Mostly going ok but hitting compilation issues around recent(last 9 months) changes to mapnik_symbolizer.

Doesn't seem to be related to the v3.0.x branch - is the mapnik version I'm getting from MASON_BUILD attempt out of sync with master?

src/mapnik_symbolizer.cpp:93:38: error: no member named 'target_scaling_method' in 'mapnik::property_types';

src/mapnik_symbolizer.cpp:96:38: error: no member named 'target_smooth_algorithm' in 'mapnik::property_types';

src/mapnik_symbolizer.cpp:108:38: error: no member named 'target_line_pattern' in 'mapnik::property_types'

src/mapnik_symbolizer.cpp:97:14: error: duplicate case value 'target_simplify_algorithm'

src/mapnik_symbolizer.cpp:96:14: note: previous case defined here`

Trying to step back a few commits to see if this resolves the above issue.,,