Tests:
Fix for this bug: <https://bugs.webkit.org/show_bug.cgi?id=58925> REGRESSION(r55762): Highlight color can't be copied in gmail.
Expected Results:
The pasted text should have the same background color as the copied text. To run the test manually, select each of the two words with the same background color, copy, move the selection at the end of the second word and paste.
Red background
Green background
Transparent background