[ivi-tct][webapi] Add 1 test for drag and drop

- Add addElement of DataTransfer interface

Impacted tests(approved): new 1, update 0, delete 0
Unit test platform: [IVI] crosswalk-10.39.233, t-e-c 0.120
Unit test result summary: pass 1, fail 0, block 0
This test will likely get TIMEOUT.

Could you please integrate a test from the W3C web-platform-tests? See

```
web-platform-tests$ grep 'addElement' -r *
conformance-checkers/html-aria/accessible-name-updates/676.html:      function addElement() {
conformance-checkers/html-aria/accessible-name-updates/676.html:        setTimeout(addElement,1000);
html/editing/dnd/svg/063.svg:   event.dataTransfer.addElement(document.querySelectorAll('rect')[1]);}
html/editing/dnd/svg/063.svg:   event.dataTransfer.addElement(document.querySelectorAll('rect')[0]);}
html/editing/dnd/overlay/036.xhtml:             {event.dataTransfer.addElement(div[i]);}
html/editing/dnd/overlay/032.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/overlay/009.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/009.xhtml:     {event.dataTransfer.addElement(document.querySelector('strong'));}
html/editing/dnd/overlay/017.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/038.xhtml:     event.dataTransfer.addElement(document.querySelector('strong'));
html/editing/dnd/overlay/030.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/overlay/028.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/overlay/021.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/019.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/029.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/overlay/015.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/007.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/007.xhtml:     event.dataTransfer.addElement(document.querySelector('strong'));}
html/editing/dnd/overlay/005.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/005.xhtml:     event.dataTransfer.addElement(document.querySelector('strong'));}
html/editing/dnd/overlay/031.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/overlay/003.xhtml:     event.dataTransfer.addElement(document.querySelector('span'));}
html/editing/dnd/overlay/033.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/overlay/026.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/overlay/041.xhtml:     event.dataTransfer.addElement(document.querySelectorAll('canvas')[element]);}
html/editing/dnd/overlay/027.xhtml:     event.dataTransfer.addElement(document.querySelector(feedback));}
html/editing/dnd/microdata/021.html:<title>drag &amp; drop - microdata when addElement is used</title>
html/editing/dnd/microdata/021.html:    e.dataTransfer.addElement(document.getElementById('side1'));
html/editing/dnd/microdata/021.html:    e.dataTransfer.addElement(document.getElementById('side2'));
```