Google Chrome Portable creates folders in AppData\Local\
Full path of folders:
C:\Users\nick\AppData\Local\Google\Chrome\User Data\Crashpad\reports
In User Data i have file CrashpadMetrics-active.pma
In Crashpad i have 2 files metadata and settings.dat
Other folders is empty.
I use Version 56.0.2924.87 x64 for Windows.
I fully clear my old non-portable chrome before installing portable version.
After i close portable chrome these folders disappears.