Autotools should default to WebKitBuild as the default build directory. This should avoid littering the source dir with object files and other build artifacts.
Usually the build directory is the current directory you are in when invoking configure or autogen.sh.
I looked at a few autogen.sh scripts, and they always use the current working directory as the objdir.
However, there could be a higher level script which would create the WebKitBuild directory, and launch autogen.sh or configure from there. But I'm not sure this brings a lot of added value.
We could rather correct the build documentation to use this WebKitBuild directory (once bug 16736 is fixed):
There would be:
I would say this is a characteristic of autotools. The correct way to avoid
littering the source tree, as you pointed out yourself, is to build outside of
the source tree.
Please re-open the bug if you disagree.