Izzy opined it correctly here that the only sensible place for having factory home screen layout is the launcher's APK itself.
Since I don't own a Lenovo device let alone your specific model I used my MTK device running stock 4.2.1 as the testing ground. It has stock launcher (
About that thing called factory home screen layout -- a launcher usually has one or more databases inside its
/data/data/.. directory, and one of that database has a table named
favorites (name could differ among launchers but the idea is same). (See my answer for How can I manage “desktop” icons to know what I'm talking about.)
The default setting that you see is nothing but code in the APK creating database(s) from scratch and populating the
favorites table with hard-coded entries (like "Contacts", "Phone", "Messages", "Chrome" at the dock).
E.g. See this code snippet from the source code of
The code is available here. If you look closely at few lines above the line 262, you would see that the code is creating a new database with proper schema and then populating the database with
favorites table which is available to it.
At this point, I didn't bother digging more to know, where does this
favorites table or the related content is saved, since my conclusion is drawn from custom launchers as well who also have a different but a factory layout (clearly not saved outside the APK).
I would recommend taking a look at the source code (provided that you can find it first) of your default launcher, or extract the APK and dig under
res folder. I found some interesting stuff under
Oh, if someone wants to experiment on OP's question then I suggest you do Clear Data from Settings → Apps → All apps →
<Your Launcher> since it would have the same effect as doing a factory reset (not Hard reset).