Web Inspector: Calling getEventListeners() on element with malformed javascript event listeners crashes
https://bugs.webkit.org/show_bug.cgi?id=93937

Reviewed by Pavel Feldman.

Source/WebCore:

- check listener function to be non-null (happens upon an exception while compiling attribute listeners)

* bindings/js/JSInjectedScriptHostCustom.cpp:
(WebCore::getJSListenerFunctions):
* bindings/v8/custom/V8InjectedScriptHostCustom.cpp:
(WebCore::getJSListenerFunctions):

LayoutTests:

- added test for crash on invalid syntax in an attribute JS listener;
- added custom expectation for chrome due to JS error logged to console by JSC while compiling attribute listener;

* inspector/console/command-line-api-getEventListeners-expected.txt:
* inspector/console/command-line-api-getEventListeners.html:
* platform/chromium/inspector/console/command-line-api-getEventListeners-expected.txt: Copied from LayoutTests/inspector/console/command-line-api-getEventListeners-expected.txt.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@125654 268f45cc-cd09-0410-ab3c-d52691b4dbfc