RevisionGraph: fix graph error when parents is not log list
tree382658c5f97ca4b3c447b3b1294ff47e3497f60a
-rw-r--r-- 367 .gitignore
-rw-r--r-- 543 .gitmodules
drwxr-xr-x - Languages
-rw-r--r-- 3400 build.txt
drwxr-xr-x - common
drwxr-xr-x - contrib
drwxr-xr-x - doc
drwxr-xr-x - ext
-rw-r--r-- 184 release.txt
drwxr-xr-x - src
drwxr-xr-x - test