Add CSS.setStyleText to the Web Inspector protocol.

This provides a direct path for the Safari Web Inspector to live edit whole style rules.

https://webkit.org/b/109340
rdar://problem/13337211

Reviewed by Joseph Pecoraro.

Source/WebCore:

* inspector/Inspector.json:
(CSS.setStyleText): Added.
* inspector/InspectorCSSAgent.cpp:
(InspectorCSSAgent::SetStyleTextAction):
(WebCore::InspectorCSSAgent::SetStyleTextAction::SetStyleTextAction): Added.
(WebCore::InspectorCSSAgent::SetStyleTextAction::perform): Added.
(WebCore::InspectorCSSAgent::SetStyleTextAction::undo): Added.
(WebCore::InspectorCSSAgent::SetStyleTextAction::redo): Added.
(WebCore::InspectorCSSAgent::SetStyleTextAction::mergeId): Added.
(WebCore::InspectorCSSAgent::SetStyleTextAction::merge): Added.
(WebCore::InspectorCSSAgent::SetPropertyTextAction::redo):
(WebCore::InspectorCSSAgent::setStyleText): Added.
* inspector/InspectorCSSAgent.h:
* inspector/InspectorStyleSheet.cpp:
(WebCore::InspectorStyle::getText): Added.
(WebCore::InspectorStyle::setText): Added.
(WebCore::InspectorStyleSheet::setStyleText):
(WebCore::InspectorStyleSheetForInlineStyle::setStyleText):
* inspector/InspectorStyleSheet.h:
(WebCore::InspectorStyle::styleText): Added as an alias to getText.
(WebCore::InspectorStyle::applyStyleText): Added as an alias to setText.

LayoutTests:

* inspector/styles/styles-new-API-expected.txt: Updated.
* inspector/styles/styles-new-API.html: Test CSSAgent.setStyleText.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@148723 268f45cc-cd09-0410-ab3c-d52691b4dbfc