Remove draft comment icons from 'Patch Sets' drop-down panel

If a user adds/removes draft comments on any patch set, and there was
no other modification of the change, then the change detail is not
reloaded and as result the draft comment icons shown in the 'Patch
Sets' drop-down panel may be outdated. The draft comment icon may be
shown for patch sets that have no draft comments, and it may be
missing for patch sets that have draft comments. This turns these
icons useless.

To fix this the change detail would need to be reloaded if there was
any change to the draft comment status of a patch set. At the moment
the reload doesn't happen because the ETag of the change doesn't
include the draft comment status of the patch sets. Including the
draft comment status into the ETag computation would be expensive
since this would require one SQL statement per patch set to load the
draft comments from the database.

Since the 'Reply' button is now always highlighted when there are
draft comments on any patch set the draft comment icons in the 'Patch
Sets' drop-down panel are not needed anymore and can be removed.
Highlighting the 'Reply' has also the advantage that users can click
on it and actually see all draft comments across all patch sets, while
the icons in the 'Patch Sets' drop-down panel only showed which patch
sets have draft comments, but not the comments themselves.

Removing the draft comment icons from the 'Patch Sets' drop-down panel
makes the loading of the panel faster because the DRAFT_COMMENTS
option is no longer needed to load the change. This option required
one SQL statement per patch set.

Bug: issue 3395
Change-Id: I1682f5a4eb420f3672041861a7a14df6daaebaee
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
4 files changed