NEON intrinsics should be used with gaussian blur filter

NEON intrinsics should be used with gaussian blur filter
https://bugs.webkit.org/show_bug.cgi?id=90166

Reviewed by Zoltan Herczeg.

Rewrite inline assembly to NEON intrinsics for better portabilty
and readibility. Remove unnecessary FEGaussianBlurNEON.cpp and add
NEONHelpers.h to the project which will contains the shared
NEON code of the filters.

Existing tests cover this issue.

* CMakeLists.txt:
* GNUmakefile.list.am:
* Target.pri:
* WebCore.gypi:
* WebCore.vcproj/WebCore.vcproj:
* WebCore.xcodeproj/project.pbxproj:
* platform/graphics/filters/FEGaussianBlur.cpp:
(WebCore::FEGaussianBlur::platformApplyGeneric):
(WebCore::FEGaussianBlur::platformApplyWorker):
* platform/graphics/filters/FEGaussianBlur.h:
(FEGaussianBlur):
* platform/graphics/filters/arm/FEGaussianBlurNEON.cpp: Removed.
* platform/graphics/filters/arm/FEGaussianBlurNEON.h:
(WebCore::boxBlurNEON):
* platform/graphics/filters/arm/NEONHelpers.h: Added.
(WebCore):
(WebCore::loadRGBA8AsFloat):
(WebCore::storeFloatAsRGBA8):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@121900 268f45cc-cd09-0410-ab3c-d52691b4dbfc