Extract StyledElementInlineStylePropertyMap from StyledElement.cpp and to its own file. Also rename it to InlineStylePropertyMap for simplicity.
Pull request: https://github.com/WebKit/WebKit/pull/7040
Committed 257292@main (3fa92bc62217): <https://commits.webkit.org/257292@main> Reviewed commits have been landed. Closing PR #7040 and removing active labels.
<rdar://problem/102910160>