Samsung Galaxy Tab 2 Not booting, Not charging and not allowing to factory-reset
I was able to recover my Samsung Galaxy Tab 2 after it came in contact of water.

Writing this in case if anyone in future faces the issue:


I Kept the device on charging for almost 6 Hours.
Next day, I kept the device in Dry and Sunny Place-Under direct Sunshine, for at about 4-5 Hours. During this "soak" exercise, the temperature was about 27-28 Degree C. 
I then turned on Device as usual(just by pressing Power key, no factory-reset), and it booted, and it reached Home Screen too. But after 2-3 Hours, it again auto-switched off.
Next day, I again repeated step-2 
Finally, after 2-3 "soak" exercise (meaning keeping device in direct sunshine), now device is working without any issue.


This is by no means a full-proof method, but the one worked for me and may help someone, just in case!!