The Clutter backend split is opaque enough that should allow us to just
build all possible backends inside the same shared object, and select
the wanted backend at initialization time.
This requires some work in the build system, as well as the
initialization code, to remove duplicate functions that might cause
conflicts at build and link time. We also need to defer all the checks
of the internal state of the platform-specific API to run-time type
checks.
The tests/accessibility, tests/micro-bench and the examples directory
in the coobook create a lot of non-installed binaries. Since we know who
they are, and we ignore them, we can auto-generate the ignore files as
well.
The rest of Clutter is covered by the main ignore file.
The required .so file was named using @CLUTTER_WINSYS@ but since
bf9d5f3949 the .so should be named with @CLUTTER_SONAME_INFIX@. This
was breaking the build on eglx.