Bug 600100, Part 1: Return a status of NS_FRAME_NOT_COMPLETE during reflow of nsBlockFrame if we have a next continuation with pushed floats to prevent crashing in columns.
Backed out changeset 3b18c328b316 (bug 600100) to fix commit message DONTBUILD.
Bug 600100, Part 1: Return a status of NS_FRAME_NOT_COMPLETE during reflow of nsBlockFrame if we have a next continuation with pushed floats to prevent crashing in columns. [r=dbaron]