ccache configure option for mozilla

On Friday I landed a patch for bug 577636, which adds an option to mozilla-central’s configure to use ccache for your build. You can just add — with-ccache=<path to ccache> to your mozconfig to begin building with ccache. Or you can just use — with-ccache=ccache if ccache is already in your path.

This was possible before by adding CC=ccache gcc and the such to your mozconfig, but hopefully the configure option is slightly more convenient for everyone. The real value is for cross compiles where we jump through a few hoops to find the right toolchain and specifying CC and the such in your mozconfig is more than a little complicated.

Update: — with-ccache=ccache no longer works. You need to either have — with-ccache or — with-ccache=absolute/path/to/ccache