Reviewed by John

    Reviewed by John

        Fix for this bug:

        <rdar://problem/3775920> REGRESSION (Mail): Centering doesn't work in HTML mail

        * khtml/css/css_computedstyle.cpp:
        (DOM::CSSComputedStyleDeclarationImpl::copyInheritableProperties): Factor out the
        implementation here into new copyPropertiesInSet helper. This now calls the
        generalized copyPropertiesInSet function with the arguments needed to make copying
        inheritable work.
        * khtml/css/css_computedstyle.h:
        * khtml/css/css_valueimpl.cpp:
        (CSSStyleDeclarationImpl::diff): Move this function here from css_computedstyle.cpp.
        In order to do apply block properties, "regular" style declarations need to do style
        diffs as well.
        (CSSStyleDeclarationImpl::copyBlockProperties): New helper. Just like copyInheritableProperties
        except that it uses a different set of properties that apply only to blocks.
        (CSSStyleDeclarationImpl::copyPropertiesInSet): New helper that looks at a style declaration
        and copies out those properties listed in a pre-defined set.
        * khtml/css/css_valueimpl.h:
        * khtml/editing/htmlediting.cpp:
        (khtml::StyleChange::StyleChange): Modified to work with style changes that apply to a whole
        block, factoring out some of the special case code that should now only run in the inline case.
        (khtml::StyleChange::init): Factored out the code that now is in checkForLegacyHTMLStyleChange.
        (khtml::StyleChange::checkForLegacyHTMLStyleChange): New helper for case where we want
        special handling for "legacy" HTML styles like <B> and <I>.
        (khtml::ApplyStyleCommand::doApply): Much refactoring in this class to divide up the work of
        style changes into different kinds. CSS specifies certain properties only apply to certain
        element types. This set of changes now recognizes two such separate cases: styles that apply
        to blocks, and styles that apply to inlines.
        (khtml::ApplyStyleCommand::applyBlockStyle): New function to handle apply styles to whole blocks.
        (khtml::ApplyStyleCommand::applyInlineStyle): New function to handle apply styles to inlines.
        (khtml::ApplyStyleCommand::isHTMLStyleNode): Is now passed a CSSStyleDeclarationImpl to work
        with rather than working on the CSSStyleDeclarationImpl member variable of the class. This is
        done so that the function can be passed a portion of the styles being applied so that block styles
        and inline styles can be handled separately.
        (khtml::ApplyStyleCommand::removeCSSStyle): Ditto.
        (khtml::ApplyStyleCommand::removeBlockStyle): New function to handle removing styles from whole blocks.
        (khtml::ApplyStyleCommand::removeInlineStyle): New function to removing styles from inlines.
        (khtml::ApplyStyleCommand::addBlockStyleIfNeeded): New function to handle applying style to whole blocks.
        (khtml::ApplyStyleCommand::addInlineStyleIfNeeded): New function to handle applying style to inlines.
        * khtml/editing/htmlediting.h:
        (khtml::StyleChange::): Changed as described above.
        (khtml::StyleChange::usesLegacyStyles):
        (khtml::EditCommand::setEndingSelectionNeedsLayout): New function to that tells the ending selection
        it needs to layout, even though it has not changed position in the DOM. For instance, this is needed
        when text align changes.
        * khtml/khtml_part.cpp:
        (KHTMLPart::setTypingStyle): Put in an early bail-out in the case where the current style matches
        the passed-in argument.
        (KHTMLPart::applyStyle): Modify this function so that block styles are applied when the selection
        is a caret. Formerly, this just set typing style and made no visible changes to the document.

        New tests.

        * layout-tests/editing/editing.js: Added some glue to change text align.
        * layout-tests/editing/style/block-style-001-expected.txt: Added.
        * layout-tests/editing/style/block-style-001.html: Added.
        * layout-tests/editing/style/block-style-002-expected.txt: Added.
        * layout-tests/editing/style/block-style-002.html: Added.
        * layout-tests/editing/style/block-style-003-expected.txt: Added.
        * layout-tests/editing/style/block-style-003.html: Added.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@7921 268f45cc-cd09-0410-ab3c-d52691b4dbfc