Bug 940170 - part 1 - constify PLDHashTableOps in layout/; r=bz
Bug 940170 - part 2 - constify PLDHashTableOps in content/; r=bz
Bug 940170 - part 3 - constify PLDHashTableOps in dom/; r=bz
Bug 940170 - part 4 - constify PLDHashTableOps in miscellaneous other places; r=bz