While creating the latest patch for Bug 11882, I noticed that I kept getting duplicate copies of all of the new webarchive layout tests and their results in the patch. The problem was that svn-create-patch saw "LayoutTests/webarchive" as a modified "file", and ran a diff on it.
The correct solution (for now) is to ignore modified directories when creating a patch.
I have a patch to fix this.
Created attachment 12777 [details]
Comment on attachment 12777 [details]
Committed revision 19256.