WebKitGTK+ 2.20 will require libbrotli for WOFF2 font support

[mcatanzaro gnome org]

Hi distros,

WebKitGTK+ has previously supported WOFF2 fonts using a bundled copy of libbrotli. Since libbrotli can now be packaged as a system library, the bundled copy has been removed and a system copy will be required beginning with WebKitGTK+ 2.20 (actually 2.19.1). You should package libbrotli for your distros if possible.

In cases where it may not be possible (e.g. frozen LTS distros), you will still be able to upgrade WebKit. You can either patch the bundled libbrotli back in, or build it as a static library in your WebKitGTK+ package, or build with -DUSE_WOFF2=OFF in order to disable WOFF2 font support and the requirement for libbrotli.

Sorry for the inconvenience.

Michael