From cursory grepping, it looks like evolution-data-server's direct use of gtk+ is limited to (a) generating documentation with gtk-doc and (b) loading gtk modules when running tests with the environment variable 'EDS_TESTING' set.
libgweather's got a harder dependency on gtk, but evolution-data-server's use of libgweather is optional and can be turned off in its configure script with --disable-gtk, which also disables its use of gcr
From cursory grepping, it looks like evolution- data-server' s direct use of gtk+ is limited to (a) generating documentation with gtk-doc and (b) loading gtk modules when running tests with the environment variable 'EDS_TESTING' set.
libgweather's got a harder dependency on gtk, but evolution- data-server' s use of libgweather is optional and can be turned off in its configure script with --disable-gtk, which also disables its use of gcr