We use a compilation symbol in our build to allow the inclusion of
specific headers while building GTK, to avoid the need to include only
the global header.
Each namespace has its own compilation symbol because we used to have
different libraries, and strict symbol visibility between libraries;
now that we have a single library, and we can use private symbols across
namespaces while building GTK, we should have a single compilation
symbol, and simplify the build rules.
Make the API expect a tranform of the proper category instead of
doing the check ourselves and returning TRUE/FALSE.
The benefit is that the mai use case is switch (transform->category)
statements and in those we know the category and don't need to check
TRUE/FALSE.
Using the wrong matrix will now cause a g_warning().
In particular, add a per-category querying API for the matrix:
- gsk_transform_to_translate()
- gsk_transform_to_affine()
- gsk_transform_to_2d()
- gsk_transform_to_matrix()
This way, code can use the relevant one for the given category.
