Chromoting Host: Don't listen for PRIMARY selection changes

Chromoting Host: Don't listen for PRIMARY selection changes

This CL makes the Chromoting host clipboard handling match what Chrome
does on Linux: it listens only for CLIPBOARD changes, but sets both
CLIPBOARD and PRIMARY selections.

This also fixes the problem of the Linux host copying PRIMARY to
CLIPBOARD: When the user mouse-selected some text, the host process
would assert CLIPBOARD ownership with that selected text. This clobbered
any previous CLIPBOARD data, and frustrated the user.

BUG=169965
TEST=manually verify clipboard contents using "xsel" or similar.

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=207734

[Lambros, 2013-06-20 22:51:42]

We could remove PRIMARY handling altogether, but I think that should be a
separate CL as it would also touch Chrome code, requiring more OWNERS approval.

[Wez, 2013-06-20 23:35:57]

On 2013/06/20 22:51:42, Lambros wrote:
> We could remove PRIMARY handling altogether, but I think that should be a
> separate CL as it would also touch Chrome code, requiring more OWNERS
approval.

LGTM, but please remove the JS Extension APIs mention from the CL description,
since it's confusing and doesn't seem to clarify anything!

[commit-bot: I haz the power, 2013-06-21 01:37:05]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/lambroslambrou@chromium.org/17513003/1

[commit-bot: I haz the power, 2013-06-21 06:27:20]

Change committed as 207734