Make RenderLayer not arena-allocated.
<https://webkit.org/b/87523>

Reviewed by Antti Koivisto.

Let RenderLayerModelObject store its RenderLayer in a unique_ptr.
Layers are relatively low-volume objects and this looks neutral
on our performance tests.

Re-landing this since the original commit exposed a problem with
the destruction order. This pattern:

    m_someRenderer->destroy();
    m_someRenderer = nullptr;

..is different from what we get with unique_ptr, which clears
the pointer storage before calling the destructor.
I believe that the new order is strictly better as it removes
one path to accessing an object that is undergoing destruction.

The exposed bug was in RLC::fixedRootBackgroundLayerChanged()
where we were dereferencing the RenderView's layer() without
checking, despite it being called below ~RenderLayer.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157333 268f45cc-cd09-0410-ab3c-d52691b4dbfc
[sh4] Add missing test32 implementation in macro assembler.
https://bugs.webkit.org/show_bug.cgi?id=122689

Patch by Julien Brianceau <jbriance@cisco.com> on 2013-10-12
Reviewed by Andreas Kling.

* assembler/MacroAssemblerSH4.h:
(JSC::MacroAssemblerSH4::test32):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157334 268f45cc-cd09-0410-ab3c-d52691b4dbfc
[sh4] Add missing spaces in JITStubsSH4.h
https://bugs.webkit.org/show_bug.cgi?id=122690

Patch by Julien Brianceau <jbriance@cisco.com> on 2013-10-12
Reviewed by Andreas Kling.

* jit/JITStubsSH4.h: Space between string concatenation is mandatory with C++11

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157335 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Make LayoutState not arena-allocated.
<https://webkit.org/b/122649>

Reviewed by Antti Koivisto.

Let RenderView own a singly-linked chain of LayoutState objects
managed by unique_ptr.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@157336 268f45cc-cd09-0410-ab3c-d52691b4dbfc