LayoutTests:

LayoutTests:

        Reviewed by levi

        <rdar://problem/4609184>
        Mail crashes at WebCore::Selection::adjustForEditableContent
        <rdar://problem/4609140>
        Crash at WebCore::Range::compareBoundaryPoints

        * editing/selection/mixed-editability-1-expected.checksum: Added.
        * editing/selection/mixed-editability-1-expected.png: Added.
        * editing/selection/mixed-editability-1-expected.txt: Added.
        * editing/selection/mixed-editability-1.html: Added.
        * editing/selection/mixed-editability-2-expected.checksum: Added.
        * editing/selection/mixed-editability-2-expected.png: Added.
        * editing/selection/mixed-editability-2-expected.txt: Added.
        * editing/selection/mixed-editability-2.html: Added.

WebCore:

        Reviewed by levi

        <rdar://problem/4609184>
        Mail crashes at WebCore::Selection::adjustForEditableContent
        <rdar://problem/4609140>
        Crash at WebCore::Range::compareBoundaryPoints

        * editing/Selection.cpp:
        (WebCore::Selection::adjustForEditableContent):
        * editing/VisiblePosition.cpp:
        (WebCore::VisiblePosition::next): Moved code into a helper function.
        (WebCore::VisiblePosition::previous): Ditto.
        * editing/htmlediting.cpp:
        (WebCore::comparePositions): Moved from Selection.cpp.
        (WebCore::lowestEditableAncestor): Added.  Returns rootEditableElement
        for a node in editable content and the rootEditableElement for the first
        ancestor that's editable for a node in non-editable content.
        (WebCore::firstEditablePositionAfterPositionInRoot):
        (WebCore::lastEditablePositionBeforePositionInRoot):
        * editing/htmlediting.h:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@15195 268f45cc-cd09-0410-ab3c-d52691b4dbfc