Fix a significant error in the accounting for pre-zeroed pages.  This is a candidate for RELENG_2_2...
Fix a significant error in the accounting for pre-zeroed pages.  This
is a candidate for RELENG_2_2...

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase