[DRE-maint] Bug#879983: ruby-cairo: Fails to build with cairo 1.15 (test failures)

[Jeremy Bicha]

Source: ruby-cairo
Version: 1.15.10-1
Severity: serious

ruby-cairo 1.15.10-1 fails to buid from source with cairo 1.15.8 which
was recently uploaded to Debian unstable.

Here's a patch that fixes one of the two test failures:
https://github.com/rcairo/rcairo/commit/d0b125e

Here's the other error:

Error: test_sub_outline(PDFSurfaceTest::#add_outline):
Cairo::TagError: invalid tag name, attributes, or nesting
/<<PKGBUILDDIR>>/test/test_pdf_surface.rb:26:in `add_outline'
/<<PKGBUILDDIR>>/test/test_pdf_surface.rb:26:in `test_sub_outline'
     23:       context.tag(Cairo::Tag::DEST, "name='destination'") do
     24:         context.show_text("Destination")
     25:       end
  => 26:       id = surface.add_outline(Cairo::PDFOutline::ROOT,
     27:                                "top-level",
     28:                                "destination",
     29:                                Cairo::PDFOutlineFlags::OPEN)


Thanks,
Jeremy Bicha