CSS.styleSheetAdded and CSS.styleSheetRemoved for multiple documents.


== Running test suite: CSS.StyleSheetEvents.MultipleDocuments
-- Running test case: CheckStyleSheets
PASS: Should be one stylesheets.
URL: inspector/css/resources/external.css <mainframe>

-- Running test case: CheckStyleSheetsAfterAddingSubframe
PASS: Should be two stylesheets.
PASS: New StyleSheet is for a subframe
URL: inspector/css/resources/external.css <mainframe>
URL: inspector/css/resources/external.css <childframe>

-- Running test case: CheckStyleSheetsAfterRemovingSubframe
PASS: Should be one stylesheet.
PASS: Removed StyleSheet is for a subframe
URL: inspector/css/resources/external.css <mainframe>