[TextureMapper] Normalize pattern transform for pattern compositing
https://bugs.webkit.org/show_bug.cgi?id=139374

Reviewed by Martin Robinson.

In CoordGfx/TexMapGL, pattern compositing (for background image) uses
the patternTransform shader uniform. However, current implementation
miscalculates its transform matrix. It uses simple rectToRect
transformationMatrix which produces unnormalized garbage term.
This causes unexpected behavior at the fragmentation stage in some
mobile GPUs.

It should calculate its scale based on tileSize and contentSize,
and its position based on tilePhase and contentSize.

No new tests because the bug only occurs on some mobile GPUs.

* platform/graphics/texmap/TextureMapperLayer.cpp:
(WebCore::TextureMapperLayer::computePatternTransformIfNeeded):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@176931 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Remove the unused WTF_USE_GCC_COMPUTED_GOTO_WORKAROUND after r129453.
https://bugs.webkit.org/show_bug.cgi?id=139373

Reviewed by Sam Weinig.

* interpreter/Interpreter.cpp:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@176932 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Use more PassRef in AtomicString.
<https://webkit.org/b/139319>

Reviewed by Antti Koivisto.

Make a pass over AtomicString and convert functions that return PassRefPtr
into returning RefPtr (where it may be null) and PassRef otherwise.
This allows the compiler to skip null checks in many places.

* wtf/text/AtomicString.cpp:
(WTF::addToStringTable):
(WTF::AtomicString::add):
(WTF::AtomicString::addFromLiteralData):
(WTF::AtomicString::addSlowCase):
* wtf/text/AtomicString.h:
(WTF::AtomicString::add):
(WTF::AtomicString::addWithStringTableProvider):
* wtf/text/cf/AtomicStringCF.cpp:
(WTF::AtomicString::add):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@176933 268f45cc-cd09-0410-ab3c-d52691b4dbfc