DFG::SpeculativeJIT::speculateNumber() should just use SpeculateDoubleOperand instead of doing its own thing
https://bugs.webkit.org/show_bug.cgi?id=110659

Reviewed by Oliver Hunt and Mark Hahnenberg.
        
This simplifies the code, and also has the effect that if speculateNumber() is called
prior to someone actually using the number in a double context, then the number will
already be up-converted to double and ready to go.

Previously if this ever came up, the subsequent use would have to again branch to see
if the value is tagged as int or tagged as double.

On the other hand, if you ever did speculateNumber() and then used the value as a
JSValue, this will be a slow down now.

I suspect that the former (speculateNumber() and then use as number) is more likely
than the latter (speculateNumber() and then use as JSValue).

* dfg/DFGSpeculativeJIT.cpp:
(JSC::DFG::SpeculativeJIT::speculateNumber):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143818 268f45cc-cd09-0410-ab3c-d52691b4dbfc
REGRESSION(r130089): Scrollbar thumb no longer re-rendered on hover
https://bugs.webkit.org/show_bug.cgi?id=109230

Source/WebCore:

In r130089, I accidentally removed the extra check that made scrollbar
parts styles sad. I put it back and made them happy.

Reviewed by Eric Seidel.

Test: fast/css/pseudo-element-selector-scrollbar-hover.html

* css/SelectorChecker.cpp:
(WebCore::SelectorChecker::match): Added the check back.

LayoutTests:

Reviewed by Eric Seidel.

* fast/css/pseudo-element-selector-scrollbar-hover-expected.html: Added.
* fast/css/pseudo-element-selector-scrollbar-hover.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143819 268f45cc-cd09-0410-ab3c-d52691b4dbfc