I don't know if this should qualify as an answer or not, but I'd like to share my findings all the same.
I looked in the console where the line was being logged and I clicked on the link to Dashboard_v6.1.0.55920.4.
From there, I followed that line back to the originating function (just by scrolling to the left).
This is where I found where the logging has originated from:
Tridion.Type.registerNamespace("Tridion.Core");Tridion.Core.MessageLog
That, in itself, wasn't too useful as that's just the message center.
So, while in this file, I did a search on "86" and "17"; these are the keycodes for "v" and "ctrl", respectively.
That's where I discovered that the tridion.constants namespace contains references to all the major keycodes we'd use in a browser. I didn't dig very deeply, but my guess is that there's a switch statement that executes. the paste command.
Then I did a search for the word "copy" and found $cme.executeCommand("Copy",a)};
That seems to execute the "copy" command, but it only appears twice. It looks like the logging actually happens elsewhere. Based on just clicking stuff, the Ribbon and the context menu log, while the key commands don't.
So I followed the function (scrolling to the left), and discovered this:
Tridion.Cme.Views.DashboardBase.prototype.onContextMenuClick
By following that, then, backwards (Scrolling to the right), I found this command, which seems to do the job of registering that console.log():
$log.debug("Executing command '{0}'",a);
So, I did a search on the copy command:
$cme.executeCommand("Copy",a)};
Looks like it's used by two function:
Tridion.Cme.Views.DashboardBase.prototype.onListItemCopy
Tridion.Cme.Views.DashboardBase.prototype.onTreeItemCopy
That's the context menu and ribbon, it would appear.
I haven't found, yet, how the keyCodes are tied to the copy command, but it appears to be different from the Ribbon and Context Menu, simply based on superficial snooping.