Add console warning for canceling uncancelable TouchEvent

Add console warning for canceling uncancelable TouchEvent

BUG=370149
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=173554

[Rick Byers, 2014-05-07 02:55:00]

pfeldman@ PTAL

[pfeldman, 2014-05-07 15:36:21]

lgtm w/ nit

https://codereview.chromium.org/273503004/diff/30001/Source/core/events/Touch...
File Source/core/events/TouchEvent.cpp (right):

https://codereview.chromium.org/273503004/diff/30001/Source/core/events/Touch...
Source/core/events/TouchEvent.cpp:100: if (!cancelable()) {
Blink's recommendation is to stack guard expressions instead of nested
conditions.

[Rick Byers, 2014-05-07 16:24:22]

On 2014/05/07 15:36:21, pfeldman wrote:
> lgtm w/ nit
> 
>
https://codereview.chromium.org/273503004/diff/30001/Source/core/events/Touch...
> File Source/core/events/TouchEvent.cpp (right):
> 
>
https://codereview.chromium.org/273503004/diff/30001/Source/core/events/Touch...
> Source/core/events/TouchEvent.cpp:100: if (!cancelable()) {
> Blink's recommendation is to stack guard expressions instead of nested
> conditions.

Done, thanks.

I also added an explanatory comment here (since to me the code is now less
obvious <grin>).

[Rick Byers, 2014-05-07 16:24:31]

The CQ bit was checked by rbyers@chromium.org

[commit-bot: I haz the power, 2014-05-07 16:25:03]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/rbyers@chromium.org/273503004/50001

[pfeldman, 2014-05-07 16:58:13]

if (!cancelable() || !view())
    return;
if (frame) {
    ...
}

does not have nested conditions either

[Rick Byers, 2014-05-07 17:24:19]

The CQ bit was unchecked by rbyers@chromium.org

[Rick Byers, 2014-05-07 17:29:17]

On 2014/05/07 16:58:13, pfeldman wrote:
> if (!cancelable() || !view())
>     return;
> if (frame) {
>     ...
> }
> 
> does not have nested conditions either

In that case, how about I just do this:

   if (!cancelable() && view() && view()->frame())
       view()->frame()->console().addMessage(...)

[Rick Byers, 2014-05-07 17:30:45]

On 2014/05/07 17:29:17, Rick Byers wrote:
> On 2014/05/07 16:58:13, pfeldman wrote:
> > if (!cancelable() || !view())
> >     return;
> > if (frame) {
> >     ...
> > }
> > 
> > does not have nested conditions either
> 
> In that case, how about I just do this:
> 
>    if (!cancelable() && view() && view()->frame())
>        view()->frame()->console().addMessage(...)

view()->frame() is trivially cheap (just returns a member), so caching the
return value doesn't seem worth the style headache :-)

[pfeldman, 2014-05-07 17:45:21]

lgtm, also looks fine!

[Rick Byers, 2014-05-07 17:46:17]

The CQ bit was checked by rbyers@chromium.org

[commit-bot: I haz the power, 2014-05-07 17:46:51]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/rbyers@chromium.org/273503004/70001

[commit-bot: I haz the power, 2014-05-07 18:27:46]

FYI, CQ is re-trying this CL (attempt #1).
Please consider checking whether the failures are real,
and report flakes to chrome-troopers@google.com.
The failing builders are:
  linux_blink_dbg on tryserver.blink

[commit-bot: I haz the power, 2014-05-07 19:35:22]

Change committed as 173554