[behavior][XWALK-3060] Add a function for Clipboard & DragandDrop

Impacted tests(approved): new 0, update 2, delete 0
Unit test platform: [IVI]
Unit test result summary: pass 0, fail 0, block 2

Block reason: fail to retrieving wgt-package/wgt-private/wgt-private-tmp root locations when running Tizen/Filesystem on IVI
Merge pull request #1431 from yunxiaoxie/bug-behavior-m

[behavior][XWALK-3060] Add a function for Clipboard & DragandDrop