Do not force a direction before we know it

WebCore does not calculate the text direction when calculating widths
the best we can do here is let the shaper guess the direction. Forcing
it to the default LTR breaks HarfbuzzNG on Arabic scripts.

Since the default HarfBuzz engine changed in 5.4, this was a regression
from 5.3.

See also https://bugs.webkit.org/show_bug.cgi?id=101440

Task-number: QTBUG-41450
Change-Id: Ia324c8e5ebd1744ce2dfaea94d5046ef1f77b483
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@theqtcompany.com>
Clear a stray ref on layers when purging GL resources

Fix a regression of 3df57f7e550a19cb4450ed3896aa51ddb38c2ed2 where
a reference to TextureMapperBackingStore would be kept in the
TextureMapperLayers after purgeGLResources(). This would crash later
on if the window would get destroyed before the
CoordinatedGraphicsScene that own those layers.

Task-number: QTBUG-40734
Change-Id: Id1a596c0f0ba9afd1e163f83c38dda939f521314
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@theqtcompany.com>
Merge remote-tracking branch 'origin/5.4.0' into 5.4

Change-Id: I3df74c8b47ff6e3d668f8b2126e6145670327d73
100% cpu usage for "transition: opacity" animation

https://bugs.webkit.org/show_bug.cgi?id=120012

Reviewed by Noam Rosenthal.

Schedule animation timer after scheduling a layer flush. This way it
won't overwrite animation timer with "0", thus avoiding 100% cpu usage.

* WebProcess/WebPage/CoordinatedGraphics/CoordinatedLayerTreeHost.cpp:
(WebKit::CoordinatedLayerTreeHost::scheduleAnimation):

Change-Id: Ia423bb1a8cb5da8f29aaa489c8023744d43119f2
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154711 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>
Fix build failure with python3

Task-number: QTBUG-33692
Change-Id: I9f0bd6411e42b7ca06710dd47e3bcae4d2605c81
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@theqtcompany.com>
Merge remote-tracking branch 'origin/5.4' into dev

Change-Id: I075d973264e841fea66d9cd64af72132cffcc0a6