Mac rebaselines; also remove some entries.

Seriously, I've had it enough. Why are people adding these entires never to rebaseline them later?

* platform/mac/TestExpectations:
* platform/mac/fast/css-generated-content/table-row-group-to-inline-expected.txt:
* platform/mac/fast/dom/HTMLImageElement/image-alt-text-expected.png:
* platform/mac/fast/dom/HTMLImageElement/image-alt-text-expected.txt:
* platform/mac/fast/encoding/utf-16-big-endian-expected.png:
* platform/mac/fast/encoding/utf-16-big-endian-expected.txt:
* platform/mac/fast/encoding/utf-16-little-endian-expected.png:
* platform/mac/fast/encoding/utf-16-little-endian-expected.txt:
* platform/mac/fast/forms/input-value-expected.png:
* platform/mac/fast/forms/input-value-expected.txt:
* platform/mac/fast/lists/inlineBoxWrapperNullCheck-expected.png:
* platform/mac/fast/lists/inlineBoxWrapperNullCheck-expected.txt:
* platform/mac/tables/mozilla/collapsing_borders/bug41262-3-expected.png:
* platform/mac/tables/mozilla/collapsing_borders/bug41262-3-expected.txt:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@150290 268f45cc-cd09-0410-ab3c-d52691b4dbfc