Given the same base OS (Linux) in Android and ChromeOS and much of the same sorts of things. The redundancy of having two teams is pretty obvious. So if everyone agrees that you're going to do both going forward (and I think this is a ringing endorsement of ChromeOS as a 'long term' bet by Google) it only makes sense to make one team out of them.
Then the question becomes who leads it? The guy who leads ChromeOS or the guy who leads Android? Andy wasn't a big fan of ChromeOS when I was there, I don't know if that changed, his passion was making a better phone experience. I don't think I ever talked to or hear Sundar speak when I was there so I don't know what he thinks about phones.
So Sundar gets the nod and Andy gets to pick his next role (or exit which isn't uncommon in these situations). I don't doubt Andy would be on the short list of a number of CEO search committees so perhaps he'll pop up as the new CEO of Sony or something.
Add to that the pressure brought on by Microsoft which runs almost the same version of OS on its phone and PC. This will allow them to innovate much faster. Google wants to be there. So even though the brand name will stay, Android as n OS will evolve to what is Chrome today. Completely controlled by Google.
The Chromium build system is also more suited to building an OS than a Java application. I'll assume that Dalvik stays, and that the Android API is supported.
The Android window manager is pretty powerful (actually underutilized on phone form factors, as it supports movable frames and overlap, though that is not apparent from using it. Chrome has it's own window manager, as well as it's own desktop UI.
One question might be what direction Google TV goes in, possible with a more exclusive partner arangement. Does it make sense to build Google TV apps on Android, or should it move to more of a web model using Chrome? (This isn't neccessarily assuming that Google TV survives as it's own product line).
I haven't seen what information has been publically released about Google Glass development, but it's UI could be accomplished equally with Android or Chrome underneath, and eventually it makes sense for them to be webapps.
Another possibility, seemingly out there, would be for Android to move towards a WebOS/FirefoxOS model where core applications are built using HTML and interfacing with exposed libraries, but Android apps would still be first class citizens.
I can't see both exist at the same time for much longer, and Android is encroaching on ChromeOS' domain much faster than the other way around.
I'm predicting that ChromeOS will be shut down within a couple of years.
But it's comforting that there are people that just think of it as just another web browser - that's the whole point, just think of it as a web browsing appliance that "just works like a browser" -- even though it's not.
Android is powered by Java apps (mostly). Java apps run in a virtual machine, just like web apps. Java apps are no more native than Chrome packaged apps.
Move Native Client for ARM into Chrome on Android (or, wait until PNaCl is ready, and move that into Chrome for Android).
Focus effort on exposing functionality currently available to native Android apps through web APIs in Chrome to make Chrome apps (using NaCl/PNaCl where that kind of performance is needed), rather than Dalvik ones, the preferred mechanism for delivering apps on Android.
At that point, Android and ChromeOS are pretty much the same thing.
That's a merge.
But would that improve the Android platform? I'm wondering if it would be confusing or complicated for users, getting some apps from play and other from the Chrome store. Having apps in the launcher and some other apps you have to run from Chrome. Although at that point Google could merge the Chrome store and Google Play and have shortcuts for Chrome apps that launch a chrome-less browser to look native. Now that I've though about it I think it could work rather well, but I'm still wondering what would be the benefit for the users of Android.
Edit: Now that I've seen vibrunazo's comment I think I get it. If Google build a web programming api that is the same as Android's programming for one is programming for the other. I think that would be truly awesome indeed, I enjoy developing for android, not so much for web.
Just add in Bellard's jslinux, and you can go 'round again.