Closes #4691, makes raw development changes display correctly whilst avoiding a possible race/reentrancy issue where precache_unmodified could be populated from two different places.
Closes #4691, makes raw development changes display correctly whilst avoiding a possible race/reentrancy issue where precache_unmodified could be populated from two different places.

jimbonator/shotwell,damianmoore/shotwell,ritchiewilson/shotwell,polymeris/shotwell,Sanva/shotwell-gsoc,abrauchli/shotwell,damianmoore/shotwell,abrauchli/shotwell,h4ck3rm1k3/shotwell,polymeris/shotwell,jimbonator/shotwell,polymeris/shotwell,Sanva/shotwell-gsoc,ritchiewilson/shotwell,ritchiewilson/shotwell,jimbonator/shotwell,h4ck3rm1k3/shotwell,h4ck3rm1k3/shotwell,abrauchli/shotwell,damianmoore/shotwell,Sanva/shotwell-gsoc