CSSStyleDeclaration.getPropertyPriority() fails for CSS shorthand properties with...

CSSStyleDeclaration.getPropertyPriority() fails for CSS shorthand properties with 'important' priority
https://bugs.webkit.org/show_bug.cgi?id=49058

Reviewed by Andreas Kling.

Source/WebCore:

CSSMutableStyleDeclaration::getPropertyPriority was not handling shorthands properly. Shorthands are
not part of the property list of the style so we need to query the longhands which are the one added
in the list. Only if the longhands have equal priority the shorthand priority is known. I also renamed
getPropertyPriority (not the CSSOM exposed method) to something more consistent with WebKit naming guidelines.

Test: fast/css/shorthand-priority.html

* css/CSSMutableStyleDeclaration.cpp:
(WebCore::CSSMutableStyleDeclaration::propertyIsImportant):
(WebCore::CSSMutableStyleDeclaration::addParsedProperty):
(WebCore::CSSMutableStyleDeclaration::getPropertyPriority):
* css/CSSMutableStyleDeclaration.h:
(CSSMutableStyleDeclaration):
* editing/EditingStyle.cpp:
(WebCore::EditingStyle::extractAndRemoveTextDirection):
(WebCore::EditingStyle::collapseTextDecorationProperties):
(WebCore::EditingStyle::conflictsWithInlineStyleOfElement):
(WebCore::setTextDecorationProperty):
* editing/RemoveCSSPropertyCommand.cpp:
(WebCore::RemoveCSSPropertyCommand::doApply):

Source/WebKit/qt:

Update the code as getPropertyPriority has been renamed to propertyIsImportant.

* Api/qwebelement.cpp:
(QWebElement::styleProperty):

LayoutTests:

* fast/css/shorthand-priority-expected.txt: Added.
* fast/css/shorthand-priority.html: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@106490 268f45cc-cd09-0410-ab3c-d52691b4dbfc