Subpixel rendering: border-radius painting falls back to rectangle when the snapped rounded rect becomes non-renderable.
https://bugs.webkit.org/show_bug.cgi?id=133491

Reviewed by Simon Fraser.

Pixel snapping can change the rectangle's size when it is on a certain subpixel position. (usually it does not)
This patch ensures that the snapped rect is still renderable by adjusting the radii as well.

Source/WebCore:
Test: fast/borders/hidpi-border-radius-with-subpixel-margin-not-renderable.html

* platform/graphics/RoundedRect.cpp:
(WebCore::RoundedRect::Radii::scale):
(WebCore::RoundedRect::pixelSnappedRoundedRectForPainting):
* platform/graphics/RoundedRect.h:

LayoutTests:
* fast/borders/hidpi-border-radius-with-subpixel-margin-not-renderable-expected.html: Added.
* fast/borders/hidpi-border-radius-with-subpixel-margin-not-renderable.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@169620 268f45cc-cd09-0410-ab3c-d52691b4dbfc
CSS JIT: Clean up StackAllocator
https://bugs.webkit.org/show_bug.cgi?id=133506

Patch by Yusuke Suzuki <utatane.tea@gmail.com> on 2014-06-05
Reviewed by Benjamin Poulain.

Cleaning up CSS JIt StackAllocator code. Sharing push / pop code and
using information provided by MacroAssembler more aggressively
to drop ifdefs.

* cssjit/StackAllocator.h:
(WebCore::StackAllocator::allocateUninitialized):
(WebCore::StackAllocator::push):
(WebCore::StackAllocator::pop):
(WebCore::StackAllocator::popAndDiscard):
(WebCore::StackAllocator::popAndDiscardUpTo):
(WebCore::StackAllocator::alignStackPreFunctionCall):
(WebCore::StackAllocator::unalignStackPostFunctionCall):
(WebCore::StackAllocator::stackUnitInBytes):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@169621 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Enable SANDBOX_EXTENSIONS build flag universally on cocoa
https://bugs.webkit.org/show_bug.cgi?id=133556

Reviewed by Alexey Proskuryakov.

Remove unnecessary iOS exception.

* WebKit2Prefix.h:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@169622 268f45cc-cd09-0410-ab3c-d52691b4dbfc