657844 - SynthesizeMouseMove calls should be disabled in fennec

Status: RESOLVED FIXED

(Core :: DOM: UI Events & Focus Handling, defect)

Description

[Oleg Romashin (:romaxa)]

While scrolling Fennec UI remote-viewport we do call SynthesizeMouseMove from PresShell::DidDoReflow http://mxr.mozilla.org/mozilla-central/source/layout/base/nsPresShell.cpp#7865

IIRC that is needed in order to update cursor position when FF scrolled with mouse wheel, but cursor stay on the same screen position (content behind cursor changed)....

I think this is just wasting CPU time Event handling, dispatching HitTest calls just for nothing on Mobile...

And I think we should find some conditions which help us to disable this for Mobile fennec UI process...

Comment 1

[Oleg Romashin (:romaxa)]

Attachment: Disable synthMouseMove for mobile

Comment 2

[Oleg Romashin (:romaxa)]

Not sure about other platforms which could use MOBILE_OPTIMIZE_GFX but possible having mouse pointer... like neetbooks et.c...
Probably it is better to make some pref, and control it per XUL application client.

Comment 3

[Oleg Romashin (:romaxa)]

Attachment: Pref version of synthMouseMove disable

should be more flexible for different platforms handling and different xulrunner applications

Comment 4

[Oleg Romashin (:romaxa)]

Attachment: Pref version of synthMouseMove disable

ups, typo bug

Comment 5

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 533311 [details] [diff] [review]
Disable synthMouseMove for mobile

Hmm.  Why is a gfx-specific define the right thing to condition this on?

Comment 6

[Oleg Romashin (:romaxa)]

Comment on attachment 533311 [details] [diff] [review]
Disable synthMouseMove for mobile

yep, I think GFX define is bad way to disable it and not flexible...

Comment 7

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 533317 [details] [diff] [review]
Pref version of synthMouseMove disable

This looks fine, but why not just make that a live pref using a bool pref cache?

Comment 8

[Oleg Romashin (:romaxa)]

Attachment: Version with cacheBool var

Comment 9

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 534080 [details] [diff] [review]
Version with cacheBool var

This is going to add a new cache on each DidReflow call.

Comment 10

[Oleg Romashin (:romaxa)]

Attachment: Version with cacheBool var v2

Did not found any static initialize function in PresShell, so I hope it is ok to reuse static condition in PresShell ctor. registeredReporter

Comment 11

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 534135 [details] [diff] [review]
Version with cacheBool var v2

r=me

Comment 12

[Daniel Holbert [:dholbert]]

http://hg.mozilla.org/projects/cedar/rev/dfeab223be6d

Comment 13

[Daniel Holbert [:dholbert]]

The push from comment 12 appears to have caused orange in mochitest-chrome on all platforms:
> layout/style/test/chrome/test_hover.html | Test timed out.
Sample log:
http://tinderbox.mozilla.org/showlog.cgi?log=Cedar/1306088180.1306089707.19816.gz
http://tbpl.mozilla.org/?tree=Cedar&rev=dfeab223be6d

Backed out:
  http://hg.mozilla.org/projects/cedar/rev/dfeab223be6d

Comment 14

[Daniel Holbert [:dholbert]]

(In reply to comment #13)
> Backed out:
>   http://hg.mozilla.org/projects/cedar/rev/dfeab223be6d

er sorry, that's the original push. backout push was:
http://hg.mozilla.org/projects/cedar/rev/8176003df609

Comment 15

[Timothy Nikkel (:tnikkel)]

If the pref isn't specified does it maybe default to returning false?

Comment 16

[Boris Zbarsky [:bzbarsky]]

Er, yes.  There's an optional third argument (I hate optional arguments) for what the default value should be, defaulting to false.  I should have caught that... :(

Comment 17

[Oleg Romashin (:romaxa)]

Attachment: Added default value

Hm, I saw in other implementations static variable initially initialized with some default value, and I though that  AddBoolPrefVarCache will take value pointer and check it's value and set it as default (we had this before somewhere in GTK API)..

But ok, here is one more default value passed

Comment 18

[Dão Gottwald [:dao]]

http://hg.mozilla.org/mozilla-central/rev/27ff48b7cf61