[GTK] GtkAdjustmentWatcher idle source not correctly handled
https://bugs.webkit.org/show_bug.cgi?id=119003

Reviewed by Martin Robinson.

GtkAdjustmentWatcher::updateAdjustmentsFromScrollbarsLater()
creates a new idle source and initializes
m_updateAdjustmentCallbackId, which is used everywhere and
specially in the destructor to cancel the source when the
GtkAdjustmentWatcher is deleted. However,
m_updateAdjustmentCallbackId is reset to 0 in
GtkAdjustmentWatcher::updateAdjustmentsFromScrollbars() only when
not returning early. This method is public and not only called by
the updateAdjustmentCallback, which means that a call to
updateAdjustmentsFromScrollbars could reset the
m_updateAdjustmentCallbackId without actually destroying the source.

* WebCoreSupport/GtkAdjustmentWatcher.cpp:
(WebKit::GtkAdjustmentWatcher::updateAdjustmentsFromScrollbars):
Cancel the adjustment later idle if it has been scheduled.
(WebKit::GtkAdjustmentWatcher::updateAdjustmentCallback): Reset
m_updateAdjustmentCallbackId.
* WebCoreSupport/GtkAdjustmentWatcher.h:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@153052 268f45cc-cd09-0410-ab3c-d52691b4dbfc
[Qt] REGRESSION(r152906) Modified fast/shapes/shape-inside/shape-inside-overflow.html ref test fails.
https://bugs.webkit.org/show_bug.cgi?id=118964

Reviewed by Andreas Kling.

I modified the test to use Ahem font. Now it's working well on Qt as well.

* fast/shapes/shape-inside/shape-inside-overflow-expected.html:
* fast/shapes/shape-inside/shape-inside-overflow.html:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@153053 268f45cc-cd09-0410-ab3c-d52691b4dbfc