Web Inspector: [Extensions API] Resource manipulations should be based on UISourceCod...

Web Inspector: [Extensions API] Resource manipulations should be based on UISourceCode thus extending Sources Panel.
https://bugs.webkit.org/show_bug.cgi?id=89868

Reviewed by Pavel Feldman.

Source/WebCore:

Extensions API is now based on both ScriptsPanel acting as a UISourceCodeProvider and ResourceTreeModel.
Extensions API resource could be for any content provider now.
Extensions API resource.setContent implementation is now based on UISourceCode editing methods.
Drive-by StyleSource insremental editing timeout fix.

* inspector/front-end/ExtensionServer.js:
(WebInspector.ExtensionServer.prototype._handleOpenURL):
(WebInspector.ExtensionServer.prototype._makeResource):
(WebInspector.ExtensionServer.prototype._onGetPageResources):
(WebInspector.ExtensionServer.prototype._getResourceContent):
(WebInspector.ExtensionServer.prototype._onGetResourceContent):
(WebInspector.ExtensionServer.prototype._onSetResourceContent):
(WebInspector.ExtensionServer.prototype._notifyResourceAdded):
(WebInspector.ExtensionServer.prototype._notifyResourceContentCommitted):
* inspector/front-end/JavaScriptSource.js:
* inspector/front-end/ScriptsPanel.js:
(WebInspector.ScriptsPanel.prototype.uiSourceCodes):
(WebInspector.ScriptsPanel.prototype.uiSourceCodeForURL):
(WebInspector.ScriptsPanel.prototype._addUISourceCode):
(WebInspector.ScriptsPanel.prototype._reset):
(WebInspector.ScriptsPanel.prototype.canShowAnchorLocation):
* inspector/front-end/StylesPanel.js:
(WebInspector.StyleSource.prototype.workingCopyCommitted):
(WebInspector.StyleSource.prototype.workingCopyChanged):
(WebInspector.StyleSource.prototype._callOrSetTimeout):
(WebInspector.StyleSource.prototype._commitIncrementalEdit):
(WebInspector.StyleSource.prototype._clearIncrementalUpdateTimer):
* inspector/front-end/UISourceCode.js:
(WebInspector.UISourceCode.prototype.requestContent):
(WebInspector.UISourceCode.prototype.workingCopy):
(WebInspector.UISourceCode.prototype.setWorkingCopy):
(WebInspector.UISourceCode.prototype.isDirty):

LayoutTests:

* http/tests/inspector/extensions-test.js:
(initialize_ExtensionsTest):
(initialize_ExtensionsTest.completeTest):
(initialize_ExtensionsTest.InspectorTest.runExtensionTests):
* http/tests/inspector/resources/extension-main.js:
* inspector/extensions/extensions-resources.html:
* inspector/styles/styles-history.html:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@121792 268f45cc-cd09-0410-ab3c-d52691b4dbfc