Mac: fix Esc-key cancellation of bookmark bar button drags.

Mac: fix Esc-key cancellation of bookmark bar button drags.

The drag would be cancelled after pressing Esc, but moving the mouse again would
cause the bookmark bar button to see a drag again and start a new drag. This
patch makes the button wait for the next mouse down.

BUG=28502
TEST=Drag bookmark bar button and keep mouse button; press Esc (and see cancellation animation); move mouse again and make sure a new drag doesn't start.

Committed: r33067

[viettrungluu, 2009-11-25 07:07:41]

Reviews welcome and appreciated from whoever's around.... Thanks.

[pink (ping after 24hrs), 2009-11-25 15:10:33]

LGTM but it makes me wonder why more cocoa objects don't have this problem if
esc during a drag continues to send mouseDragged: messages to the original
object.

[Nico, 2009-11-25 15:15:15]

LG.

Argh, pink beat me to it.

Pink: I think we have this problem because we manually do some of the dragging
code in this class to make dragging a button work. If this wouldn't use manual
dragging code but instead the event loop hack that
web_dragShouldBeginFromMouseDown:... in WebKit uses, we wouldn't have had this
problem I believe.

http://codereview.chromium.org/437055/diff/1/2
File chrome/browser/cocoa/bookmark_button.h (right):

http://codereview.chromium.org/437055/diff/1/2#newcode12
chrome/browser/cocoa/bookmark_button.h:12: BOOL beingDragged_;  // Are we being
dragged?
nearly all of these comments are useless and repeat what the code says imho. I'd
get rid of the first and third one and replace the second with "Set to true on
mouse down".

YMMV :-)

[viettrungluu, 2009-11-25 15:23:38]

I have nothing to add to what Nico said, though I too find it a bit strange that
Cocoa doesn't just eat the mouse drags. Thanks.

http://codereview.chromium.org/437055/diff/1/2
File chrome/browser/cocoa/bookmark_button.h (right):

http://codereview.chromium.org/437055/diff/1/2#newcode12
chrome/browser/cocoa/bookmark_button.h:12: BOOL beingDragged_;  // Are we being
dragged?
On 2009/11/25 15:15:15, Nico wrote:
> nearly all of these comments are useless and repeat what the code says imho.
I'd
> get rid of the first and third one and replace the second with "Set to true on
> mouse down".

I'll defend the first comment since it's not entirely obvious from |draggable_|
whether it's referring to the button being in a draggable state (which is what
|mayDragStart_| is) or to it being a draggable button. Agreed for the others.

> YMMV :-)

My mileage does vary! (It's my lead foot which causes this.)

[mrossetti, 2009-11-25 17:20:17]

LGTM

(Rossetti comes in 3rd.)