fix #931: NPE on unwatching a cache
fix #931: NPE on unwatching a cache
xiaoyanit/cgeo,schwabe/cgeo,rsudev/c-geo-opensource,Bananeweizen/cgeo,ThibaultR/cgeo,SammysHP/cgeo,tobiasge/cgeo,rsudev/c-geo-opensource,KublaikhanGeek/cgeo,Bananeweizen/cgeo,auricgoldfinger/cgeo,ThibaultR/cgeo,madankb/cgeo,KublaikhanGeek/cgeo,matej116/cgeo,lewurm/cgeo,madankb/cgeo,cgeo/cgeo,SammysHP/cgeo,KublaikhanGeek/cgeo,vishwakulkarni/cgeo,rsudev/c-geo-opensource,yummy222/cgeo,Huertix/cgeo,madankb/cgeo,kumy/cgeo,pstorch/cgeo,superspindel/cgeo,schwabe/cgeo,pstorch/cgeo,cgeo/cgeo,marco-dev/c-geo-opensource,Bananeweizen/cgeo,tobiasge/cgeo,xiaoyanit/cgeo,auricgoldfinger/cgeo,cgeo/cgeo,samueltardieu/cgeo,schwabe/cgeo,vishwakulkarni/cgeo,Huertix/cgeo,cgeo/cgeo,superspindel/cgeo,lewurm/cgeo,S-Bartfast/cgeo,lewurm/cgeo,schwabe/cgeo,brok85/cgeo,kumy/cgeo,matej116/cgeo,S-Bartfast/cgeo,marco-dev/c-geo-opensource,tobiasge/cgeo,auricgoldfinger/cgeo,kumy/cgeo,xiaoyanit/cgeo,Huertix/cgeo,marco-dev/c-geo-opensource,mucek4/cgeo,samueltardieu/cgeo,brok85/cgeo,yummy222/cgeo,superspindel/cgeo,ThibaultR/cgeo,yummy222/cgeo,mucek4/cgeo,samueltardieu/cgeo,matej116/cgeo,SammysHP/cgeo,pstorch/cgeo,S-Bartfast/cgeo,brok85/cgeo,mucek4/cgeo,vishwakulkarni/cgeo