https://bugs.webkit.org/show_bug.cgi?id=80321

Reviewed by Dirk Schulze.

Source/WebCore: 

The code in ImageBuffer::transformColorSpace had two problems that are
fixed by this patch.

First, it was using member variables for data
that is static constant. This is incredibly wasteful, as every
ImageBuffer that is created (and we make a lot of them) gets its own
copy of the LUT and the table is initialized again and again. The
patch replaces this with a static local, with lazy evaluation, in
the method that uses the tables.

Second, the code for filling the table was mapping 255 to 254, thus
reducing the intensity and alpha of every image it pushed through a
color transform.

Test: svg/filters/color-space-conversion.svg

* platform/graphics/ImageBuffer.cpp:
(WebCore::ImageBuffer::transformColorSpace):
* platform/graphics/ImageBuffer.h:
(ImageBuffer):

LayoutTests: 

Temporarily marking Chromium tests expected to fail as a result of this patch. And a new test.

* platform/chromium/TestExpectations:
* svg/filters/color-space-conversion.svg:
* svg/filters/color-space-conversion-expected.svg:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@119831 268f45cc-cd09-0410-ab3c-d52691b4dbfc