Make a test not depend on system settings.

Make a test not depend on system settings.

On MacOS, the test fails if the system-wide preferred scroller style is
overlay.

BUG=

Committed: https://crrev.com/1d019b7c5a7d8f0cde403056e648a403814d6d10
Cr-Commit-Position: refs/heads/master@{#372906}

[Alexander Semashko, 2016-01-28 09:31:09]

ahest@yandex-team.ru changed reviewers:
+ sievers@chromium.org

[no sievers, 2016-01-30 00:18:48]

Description was changed from

==========
Make a test not depend on system settings.

On MacOS, the test fails if the system-wide preferred scroller style is
overlay.

BUG=
==========

to

==========
Make a test not depend on system settings.

On MacOS, the test fails if the system-wide preferred scroller style is
overlay.

BUG=
==========

[no sievers, 2016-01-30 00:18:48]

sievers@chromium.org changed reviewers:
+ tapted@chromium.org

[no sievers, 2016-01-30 00:19:01]

-> tapted@

[tapted, 2016-01-31 23:33:13]

https://codereview.chromium.org/1642553004/diff/1/content/browser/theme_helpe...
File content/browser/theme_helper_mac.h (right):

https://codereview.chromium.org/1642553004/diff/1/content/browser/theme_helpe...
content/browser/theme_helper_mac.h:16: class CONTENT_EXPORT
ScopedPreferredScrollerStyleOveride {
ObjectiveC gives us a cheaty way to do this kind of stuff without affecting
production code, which is what we typicallly do. It's also likely we'll need
this elsewhere in ui, so I think it should go in

ui/base/test/scoped_preferred_scroller_style_mac.h

note it shouldn't/can't then have a blink:: dependency there, but that won't
matter.

See ui/base/test/scoepd_fake_nswindow_focus.h for something to cargo cult.
You'll end up with something like this (in the .mm)

...

#include ..sdk_forward_declarations.h

// Donates a testing implementation of +[NSScroller preferredScrollerStyle].
@interface FakeNSScrollerStyleDonor : NSObject
@end

@implementation FakeNSWindowFocusDonor

+ (NSScrollerStyle)preferredScrollerStyle {
  return NSScrollerStyleLegacy;
}

@end

namespace .... {

ScopedPreferredScrollerStyle::ScopedPreferredScrollerStyle() {
  if (![NSScroller respondsToSelector:@selector(preferredScrollerStyle)])
    return;
 
    swizzler_.reset(
          new ScopedObjCClassSwizzler([NSScroller class],
                                      [FakeNSScrollerStyleDonor class],
                                      @selector(preferredScrollerStyle)));

  /* use NSNotificaitonCenter to notify ScrollbarPrefsObserver */

}

https://codereview.chromium.org/1642553004/diff/1/content/browser/theme_helpe...
content/browser/theme_helper_mac.h:18:
ScopedPreferredScrollerStyleOveride(blink::ScrollerStyle value);
nit: explicit

https://codereview.chromium.org/1642553004/diff/1/content/browser/theme_helpe...
content/browser/theme_helper_mac.h:25: };
nit: DISALLOW_COPY_AND_ASSIGN(..)

[Alexander Semashko, 2016-02-01 15:56:31]

Thanks, changed it to use swizzling.

[tapted, 2016-02-01 23:30:20]

sweet! lgtm % nit.

https://codereview.chromium.org/1642553004/diff/20001/ui/base/test/scoped_pre...
File ui/base/test/scoped_preferred_scroller_style_legacy_mac.mm (right):

https://codereview.chromium.org/1642553004/diff/20001/ui/base/test/scoped_pre...
ui/base/test/scoped_preferred_scroller_style_legacy_mac.mm:41: NSInteger
previousStyle = [NSScroller preferredScrollerStyle];
nit: previousStyle -> previous_style (there's exceptions, but we typically only
declare things with camelCase between @{interface,implementation}/@end)

[Alexander Semashko, 2016-02-01 23:40:48]

https://codereview.chromium.org/1642553004/diff/20001/ui/base/test/scoped_pre...
File ui/base/test/scoped_preferred_scroller_style_legacy_mac.mm (right):

https://codereview.chromium.org/1642553004/diff/20001/ui/base/test/scoped_pre...
ui/base/test/scoped_preferred_scroller_style_legacy_mac.mm:41: NSInteger
previousStyle = [NSScroller preferredScrollerStyle];
On 2016/02/01 23:30:20, tapted wrote:
> nit: previousStyle -> previous_style (there's exceptions, but we typically
only
> declare things with camelCase between @{interface,implementation}/@end)

Done.

[Alexander Semashko, 2016-02-01 23:41:07]

The CQ bit was checked by ahest@yandex-team.ru

[Alexander Semashko, 2016-02-01 23:41:07]

The patchset sent to the CQ was uploaded after l-g-t-m from tapted@chromium.org
Link to the patchset: https://codereview.chromium.org/1642553004/#ps40001
(title: "Fix naming nit.")

[commit-bot: I haz the power, 2016-02-01 23:42:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1642553004/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1642553004/40001

[commit-bot: I haz the power, 2016-02-01 23:58:41]

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

[commit-bot: I haz the power, 2016-02-01 23:58:42]

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

[no sievers, 2016-02-02 00:54:02]

lgtm stamp

[Alexander Semashko, 2016-02-02 07:17:52]

The CQ bit was checked by ahest@yandex-team.ru

[commit-bot: I haz the power, 2016-02-02 07:18:04]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1642553004/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1642553004/40001

[commit-bot: I haz the power, 2016-02-02 07:24:55]

Description was changed from

==========
Make a test not depend on system settings.

On MacOS, the test fails if the system-wide preferred scroller style is
overlay.

BUG=
==========

to

==========
Make a test not depend on system settings.

On MacOS, the test fails if the system-wide preferred scroller style is
overlay.

BUG=
==========

[commit-bot: I haz the power, 2016-02-02 07:24:55]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-02-02 07:26:25]

Description was changed from

==========
Make a test not depend on system settings.

On MacOS, the test fails if the system-wide preferred scroller style is
overlay.

BUG=
==========

to

==========
Make a test not depend on system settings.

On MacOS, the test fails if the system-wide preferred scroller style is
overlay.

BUG=

Committed: https://crrev.com/1d019b7c5a7d8f0cde403056e648a403814d6d10
Cr-Commit-Position: refs/heads/master@{#372906}
==========

[commit-bot: I haz the power, 2016-02-02 07:26:26]

Patchset 3 (id:??) landed as
https://crrev.com/1d019b7c5a7d8f0cde403056e648a403814d6d10
Cr-Commit-Position: refs/heads/master@{#372906}

[msw, 2016-02-02 23:18:12]

This caused SitePerProcessBrowserTest.FrameOwnerPropertiesPropagationScrolling
to start failing on Mac10.6 Tests:
https://build.chromium.org/p/chromium.mac/builders/Mac10.6%20Tests/builds/11632
Trent said he'll take a look; please fix or revert soonish; thanks!.

[tapted, 2016-02-02 23:21:53]

On 2016/02/02 23:18:12, msw wrote:
> This caused SitePerProcessBrowserTest.FrameOwnerPropertiesPropagationScrolling
> to start failing on Mac10.6 Tests:
>
https://build.chromium.org/p/chromium.mac/builders/Mac10.6%20Tests/builds/11632
> Trent said he'll take a look; please fix or revert soonish; thanks!.

fix is in https://codereview.chromium.org/1664523002 - It's just 10.6 which we
care increasingly less about.. (but still don't want a red bot just yet)