Fixed <rdar://problem/5741440> REGRESSION (r28496): After deactivating JavaScript, scripts embedded in the HTML page continue to run
     
        Before this patch, Frame::scriptProxy() would only return null in the case that javascript was 
        disabled and if the script proxy field wasn't set (which would only be the case if the window 
        hasn't loaded anything yet).  Not all callers of scriptProxy() always check for a non-null return 
        value.  Those that did check would effectively be checking if javascript was enabled before proceeding.
        This fix consists of 2 elements: first, make sure that scriptProxy() will never return null, regardless 
        of whether javascript is disabled.  This will mean that callers who don't check for null won't crash.  
        Second, callers who did check for null now instead check for javascript being disabled.  This means that 
        code paths intended for preventing javascript from being run will be making the correct check.  Another
        minor addition to this patch is that I added a function on Frame to be a shortcut for checking if javascript
        is enabled. 

        * bindings/js/JSCustomSQLStatementCallback.cpp:
        (WebCore::JSCustomSQLStatementCallback::handleEvent):
        * bindings/js/JSCustomSQLStatementErrorCallback.cpp:
        (WebCore::JSCustomSQLStatementErrorCallback::handleEvent):
        * bindings/js/JSCustomSQLTransactionCallback.cpp:
        (WebCore::JSCustomSQLTransactionCallback::handleEvent):
        * bindings/js/JSCustomSQLTransactionErrorCallback.cpp:
        (WebCore::JSCustomSQLTransactionErrorCallback::handleEvent):
        * bindings/js/JSCustomVoidCallback.cpp:
        (WebCore::JSCustomVoidCallback::handleEvent):
        * bindings/js/JSCustomXPathNSResolver.cpp:
        (WebCore::JSCustomXPathNSResolver::lookupNamespaceURI):
        * bindings/js/ScheduledAction.cpp:
        (WebCore::ScheduledAction::execute):
        * bindings/js/kjs_events.cpp:
        (WebCore::JSAbstractEventListener::handleEvent):
        (WebCore::JSLazyEventListener::parseCode):
        * bindings/js/kjs_html.cpp:
        (WebCore::runtimeObjectImplementsCall):
        * bindings/js/kjs_proxy.cpp:
        (WebCore::KJSProxy::isEnabled):
        * bindings/js/kjs_proxy.h:
        * bindings/js/kjs_window.cpp:
        (KJS::Window::retrieveWindow):
        (KJS::Window::retrieve):
        * dom/Document.cpp:
        (WebCore::Document::createHTMLEventListener):
        * dom/EventTarget.cpp:
        (WebCore::EventTarget::dispatchGenericEvent):
        * html/HTMLPlugInElement.cpp:
        (WebCore::HTMLPlugInElement::createNPObject):
        * html/HTMLScriptElement.cpp:
        (WebCore::HTMLScriptElement::evaluateScript):
        * html/HTMLTokenizer.cpp:
        (WebCore::HTMLTokenizer::parseTag):
        (WebCore::HTMLTokenizer::processToken):
        * loader/FrameLoader.cpp:
        (WebCore::FrameLoader::executeScript):
        (WebCore::FrameLoader::userGestureHint):
        (WebCore::FrameLoader::open):
        (WebCore::FrameLoader::dispatchWindowObjectAvailable):
        (WebCore::FrameLoader::switchOutLowBandwidthDisplayIfReady):
        * manual-tests/disable-javascript-reload.html: Added.
        * page/Frame.cpp:
        (WebCore::Frame::scriptProxy):
        (WebCore::Frame::bindingRootObject):
        (WebCore::Frame::windowScriptNPObject):
        * page/Frame.h:
        * page/InspectorController.cpp:
        (WebCore::canPassNodeToJavaScript):
        * page/mac/FrameMac.mm:
        (WebCore::Frame::windowScriptObject):
        * svg/SVGDocumentExtensions.cpp:
        (WebCore::SVGDocumentExtensions::createSVGEventListener):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@30325 268f45cc-cd09-0410-ab3c-d52691b4dbfc