Use refs for non-null GraphicsContext, Scrollbar, etc. in scrollbar related code

Use refs for non-null GraphicsContext, Scrollbar, etc. in scrollbar related code

R=chrishtr@chromium.org, pdr@chromium.org

Committed: https://crrev.com/0eabbb80369d664feb34db3ea4e3f9247f535e95
Cr-Commit-Position: refs/heads/master@{#364234}

[Xianzhu, 2015-12-09 17:26:48]

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

[Xianzhu, 2015-12-09 17:26:49]

Except for the noted places, all changed places are just simple changes like
'Type*' to 'Type&', 'this' to '*this', '&' to '', '->' to '.', etc.

https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp (right):

https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp:406: void
ScrollableArea::setScrollbarNeedsPaintInvalidation(ScrollbarOrientation
orientation)
This is changed to use orientation because the implementation of the method
doesn't actually require a scrollbar. Simply converting the parameter to
Scrollbar& may break some callers when the scrollbar is null.

https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.h (right):

https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.h:58: int
thumbThickness() { return m_thumbThickness; }
The caller (VisualViewport::setupScrollbar()) need to get thumb thickness
setting before creating the actual scrollbar, but
ScrollbarTheme::thumbThickness() requires a scrollbar to calculate the
thickness. Add this method to allow callers to access the setting without a
scrollbar.

https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.h:63: static
ScrollbarThemeOverlay& mobileTheme();
This allows callers to access thumbThickness().

[Xianzhu, 2015-12-09 17:29:54]

Will upload new patch sets to fix mac and windows build failures based on the
try bot results.

[pdr., 2015-12-09 17:29:59]

On 2015/12/09 at 17:26:49, wangxianzhu wrote:
> Except for the noted places, all changed places are just simple changes like
'Type*' to 'Type&', 'this' to '*this', '&' to '', '->' to '.', etc.
> 
>
https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
> File third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp (right):
> 
>
https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
> third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp:406: void
ScrollableArea::setScrollbarNeedsPaintInvalidation(ScrollbarOrientation
orientation)
> This is changed to use orientation because the implementation of the method
doesn't actually require a scrollbar. Simply converting the parameter to
Scrollbar& may break some callers when the scrollbar is null.
> 
>
https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
> File third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.h
(right):
> 
>
https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
> third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.h:58: int
thumbThickness() { return m_thumbThickness; }
> The caller (VisualViewport::setupScrollbar()) need to get thumb thickness
setting before creating the actual scrollbar, but
ScrollbarTheme::thumbThickness() requires a scrollbar to calculate the
thickness. Add this method to allow callers to access the setting without a
scrollbar.
> 
>
https://codereview.chromium.org/1511003003/diff/20001/third_party/WebKit/Sour...
> third_party/WebKit/Source/platform/scroll/ScrollbarThemeOverlay.h:63: static
ScrollbarThemeOverlay& mobileTheme();
> This allows callers to access thumbThickness().

Looks like there's a minor compile failure, but this change looks right to me %
compiler. LGTM

[chrishtr, 2015-12-09 17:35:18]

lgtm

[Xianzhu, 2015-12-09 19:34:53]

The CQ bit was checked by wangxianzhu@chromium.org

[Xianzhu, 2015-12-09 19:34:53]

The patchset sent to the CQ was uploaded after l-g-t-m from
chrishtr@chromium.org, pdr@chromium.org
Link to the patchset: https://codereview.chromium.org/1511003003/#ps100001
(title: "Final one fixing mac build")

[commit-bot: I haz the power, 2015-12-09 19:37:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1511003003/100001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1511003003/100001

[commit-bot: I haz the power, 2015-12-09 19:58:44]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-12-09 19:58:45]

Try jobs failed on following builders:
  linux_android_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_android_r...)
  mac_chromium_rel_ng on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[Xianzhu, 2015-12-09 20:19:21]

The CQ bit was checked by wangxianzhu@chromium.org

[Xianzhu, 2015-12-09 20:19:22]

The patchset sent to the CQ was uploaded after l-g-t-m from
chrishtr@chromium.org, pdr@chromium.org
Link to the patchset: https://codereview.chromium.org/1511003003/#ps120001
(title: "yet another mac fix")

[commit-bot: I haz the power, 2015-12-09 20:20:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1511003003/120001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1511003003/120001

[commit-bot: I haz the power, 2015-12-09 21:49:17]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-12-09 21:49:19]

Try jobs failed on following builders:
  linux_chromium_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  mac_chromium_rel_ng on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[Xianzhu, 2015-12-09 22:10:30]

The CQ bit was checked by wangxianzhu@chromium.org

[commit-bot: I haz the power, 2015-12-09 22:14:01]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1511003003/120001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1511003003/120001

[commit-bot: I haz the power, 2015-12-10 00:38:55]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-12-10 00:38:56]

Try jobs failed on following builders:
  linux_chromium_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[commit-bot: I haz the power, 2015-12-10 00:44:13]

Description was changed from

==========
Use refs for non-null GraphicsContext, Scrollbar, etc. in scrollbar related code
==========

to

==========
Use refs for non-null GraphicsContext, Scrollbar, etc. in scrollbar related code

R=chrishtr@chromium.org, pdr@chromium.org

Committed: https://crrev.com/0eabbb80369d664feb34db3ea4e3f9247f535e95
Cr-Commit-Position: refs/heads/master@{#364234}
==========

[commit-bot: I haz the power, 2015-12-10 00:44:15]

Patchset 7 (id:??) landed as
https://crrev.com/0eabbb80369d664feb34db3ea4e3f9247f535e95
Cr-Commit-Position: refs/heads/master@{#364234}