Cleanup bitfield accessors for slimming paint v2

Cleanup bitfield accessors for slimming paint v2

This is a preparation for a series of paint invalidation changes
for slimming paint v2.

- Combine layoutDidGetCalledSinceLastFrame into
  mayNeedPaintInvalidation because we handle them in the same way;

- Separate shouldCheckForChildPaintInvalidation from
  mayNeedPaintInvalidation to meet future slimming paint v2 needs;

- Mark some bit fields for future removal for slimming paint v2;

- Use direct m_bitfields access for private and simple setting and
  clearing of paint invalidation flags.

BUG=510908
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=201024

[Xianzhu, 2015-08-20 22:27:10]

wangxianzhu@chromium.org changed reviewers:
+ leviw@chromium.org, pdr@chromium.org

[leviw_travelin_and_unemployed, 2015-08-20 22:52:03]

Please fix all the TODO's.

LGTM. I like this distinction :)

https://codereview.chromium.org/1302993003/diff/60001/Source/core/layout/Layo...
File Source/core/layout/LayoutBlockFlow.cpp (right):

https://codereview.chromium.org/1302993003/diff/60001/Source/core/layout/Layo...
Source/core/layout/LayoutBlockFlow.cpp:389: setEverHadLayout();
This doesn't seem related to Slimming Paint v2 (not that I don't think it's a
good change, just that you may want to change your title)

https://codereview.chromium.org/1302993003/diff/60001/Source/core/layout/Layo...
File Source/core/layout/LayoutObject.h (right):

https://codereview.chromium.org/1302993003/diff/60001/Source/core/layout/Layo...
Source/core/layout/LayoutObject.h:1356:
ADD_BOOLEAN_BITFIELD(shouldInvalidateOverflowForPaint,
ShouldInvalidateOverflowForPaint); // TODO: Remove for slimming paint v2.
Nit: TODO's should have your username.

[pdr., 2015-08-20 23:01:27]

I like this cleanup in general.

I'm not a fan of removing the setters / clearers of m_bitfields though. For
example:
m_bitfields.setNormalChildNeedsLayout(false);
m_bitfields.setNeedsPositionedMovementLayout(false);
setMayNeedPaintInvalidation();
...

I can imagine someone accidentally refactoring this into the following bug:
m_bitfields.setNormalChildNeedsLayout(false);
m_bitfields.setNeedsPositionedMovementLayout(false);
m_bitfields.setMayNeedPaintInvalidation(false);
...

[Xianzhu, 2015-08-21 17:35:35]

Uploaded a new patch covering only cleanups needed by slimming paint only. Ptal.

Will create another patch for LayoutObject friends.

[leviw_travelin_and_unemployed, 2015-08-21 18:35:55]

Still fine with me.

https://codereview.chromium.org/1302993003/diff/80001/Source/core/layout/Layo...
File Source/core/layout/LayoutObject.cpp (right):

https://codereview.chromium.org/1302993003/diff/80001/Source/core/layout/Layo...
Source/core/layout/LayoutObject.cpp:1284: // TODO(wangxianzhu): Remove this for
slimming paint v2 because we don't care about paint invalidation rects.
s/don't/won't/?

[pdr., 2015-08-21 18:37:36]

On 2015/08/21 at 18:35:55, leviw wrote:
> Still fine with me.
> 
>
https://codereview.chromium.org/1302993003/diff/80001/Source/core/layout/Layo...
> File Source/core/layout/LayoutObject.cpp (right):
> 
>
https://codereview.chromium.org/1302993003/diff/80001/Source/core/layout/Layo...
> Source/core/layout/LayoutObject.cpp:1284: // TODO(wangxianzhu): Remove this
for slimming paint v2 because we don't care about paint invalidation rects.
> s/don't/won't/?

LGTM 2

[Xianzhu, 2015-08-21 19:40:01]

https://codereview.chromium.org/1302993003/diff/80001/Source/core/layout/Layo...
File Source/core/layout/LayoutObject.cpp (right):

https://codereview.chromium.org/1302993003/diff/80001/Source/core/layout/Layo...
Source/core/layout/LayoutObject.cpp:1284: // TODO(wangxianzhu): Remove this for
slimming paint v2 because we don't care about paint invalidation rects.
On 2015/08/21 18:35:55, leviw wrote:
> s/don't/won't/?

Done.

[Xianzhu, 2015-08-21 19:40:04]

The CQ bit was checked by wangxianzhu@chromium.org

[Xianzhu, 2015-08-21 19:40:05]

The patchset sent to the CQ was uploaded after l-g-t-m from leviw@chromium.org,
pdr@chromium.org
Link to the patchset: https://codereview.chromium.org/1302993003/#ps100001
(title: " ")

[commit-bot: I haz the power, 2015-08-21 19:40:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1302993003/100001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1302993003/100001

[commit-bot: I haz the power, 2015-08-21 23:04:58]

Committed patchset #6 (id:100001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=201024