A few follow-up questions:
- Could you please post the contens of chrome://policy ?
- Did you set RoamingProfileLocation or leave it unset?
- Where exactly did you look in the Roaming profile?
- Have you also checked the Roaming profile after logging out / exiting chrome?
Thanks.

@pastarmovj: Julian, would you please take a look? Thanks.

Chrome://polciy
Applies to	Level	Source	Policy name	Policy value	Status
Current user	Mandatory	Platform	AllowDinosaurEasterEgg	false	OK
Current user	Mandatory	Platform	BackgroundModeEnabled	false	OK
Current user	Mandatory	Platform	BrowserAddPersonEnabled	false	OK
Current user	Mandatory	Platform	BrowserGuestModeEnabled	false	OK
Current user	Mandatory	Platform	CloudPrintProxyEnabled	false	OK
Current user	Mandatory	Platform	CloudPrintSubmitEnabled	false	OK
Current user	Mandatory	Platform	DefaultBrowserSettingEnabled	false	OK
Current user	Mandatory	Platform	HardwareAccelerationModeEnabled	true	OK
Current user	Mandatory	Platform	HideWebStoreIcon	true	OK
Current user	Mandatory	Platform	MetricsReportingEnabled	false	OK
Current user	Mandatory	Platform	RoamingProfileSupportEnabled	true	OK
Current user	Mandatory	Platform	ShowAppsShortcutInBookmarkBar	false	OK
Current user	Mandatory	Platform	ShowHomeButton	true	OK
Current user	Mandatory	Platform	SyncDisabled	true	OK
Current user	Mandatory	Platform	WelcomePageOnOSUpgradeEnabled	false	OK

- Currently I don't set the RoamingProfileLocation option. I also did some test with the option with the same results

- Profile path I'm looking at: c:\users\username\appdata\roaming

- I did check the porfile after logging out / exiting chrome.

Hi,
Thanks for reporting this!

Can you please run Chrome with the --enable-logging flag on and also load chrome://sync-internals and check 
"Local sync backend enabled" status and the "Local backend path" values in the "Local State" section. Those should be set to "True" and the corresponding path to the roaming profile file.

Best,
Julian

Chrome://snyc-internals results:
Local State
Server Connection	not attempted
Last Synced	Never
Sync First-Time Setup Complete	false
Sync Backend Initialization	Not started
Syncing	false
Local sync backend enabled	true
Local backend path	Uninitialized

I'm wokring on the logging.

Hey sorry you don't have to dig deeper I now checked the full policy list you submitted above.

You have "SyncDisabled	true" which disables sync but this feature is built on Sync and needs it enabled to run. When local sync is on there is no way sync will talk to google servers as the roaming profile backend completely replaces the server based one. Please remove this policy and try again.

Sorry for not spotting this before.

Now. It's working. I have a Profile.pb file in ..\Appdata\Roaming\Google\Chrome\userdata\Default.

Thank you for helping me with this.

Happy that it worked! 

We are really keen on your feedback as we are rolling this new feature. It still has some limitations but we believe it has huge opportunity to help in corp environments that can't use Google Sync but regularly need to roam users between multiple machines. :)

Marking this one fixed for now.

I'm a bit confused about this policy description at https://www.chromium.org/administrators/policy-list-3#RoamingProfileSupportEnabled
Would you please explain this part:
"Google Sync is automatically disabled when this policy is enabled.
To prevent accidental data leaks it is advisable to also set the Google Chrome policy to False."?
What is "Google Chrome policy"?

Sorry this was a mistake caused by an issue with the markup in the source file for this documentation. I corrected the webpage. The text should read

"To prevent accidental data leaks it is advisable to also set the SigninAllowed policy to False."

in other words disable the signing in to Chrome if you want to be certain no other services that require Google account are enabled. This is not required to use this policy it is also a note for people that are trying to disable all Google services.

Thank you!

But SigninAllowed policy is "deprecated, consider using SyncDisabled instead" :)
It was removed from group policy templates since version 40.

IMO, it is not a good advise to disable SigninAllowed there, because RoamingProfileSupportEnabled works only without SyncDisabled (which is worth to mention instead).

The sign-in allowed will be revived most probably this comment was put there with this in mind but we will consider changing the text to reduce the chance for misunderstandings. 

Thanks for the awesome comments! :)

Thanks for response, there's more :)

I've made some tests and found out that once SyncDisabled was set to Enable, reverting it back to "Disabled" or "Not configured" doesn't restore local sync functionality.

Steps to reproduce:

 1. Set RoamingProfileSupportEnabled to Enabled
 2. Set SyncDisabled to Not configured
 3. Delete Chrome user profile (to start from blank)
 4. Update & check policy, start Chrome
 5. Everything is ok, local sync creates roaming profile file at %AppData%\Roaming\...

 6. Set SyncDisabled to Enabled
 7. Update & check policy, start Chrome
 8. Local sync not working (it is expected): "Local sync backend enabled: true, Local backend path: Uninitialized"

 9. Set SyncDisabled back to Not configured (or Disabled)
10. Update & check policy, start Chrome
11. Local sync not working: "Local sync backend enabled: true, Local backend path: Uninitialized"

Killing Chrome profile "fixes" this issue.

Tested on Chrome 57.0.2987.133 (x64), Windows 7.

Thanks for testing this and catching this interesting edge case! I have not considered this test before :)

I filed https://bugs.chromium.org/p/chromium/issues/detail?id=707181 to track that particular issue.