Crash in V8 bindings when calling Frame.LoadUrl

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Run the wxpython.py example
2. Run the "Browser object" LoadUrl popup test (which calls Frame.LoadUrl under 
the hood)
3. Run the LoadUrl popup test again, crash!

When javascript bindings were disabled by removing the `SetJavascriptBindings` 
method, it stopped crashing.

Logs:

    [wxpython.py] LoadHandler::OnLoadEnd()
        frame url = data:text/html,Test#Browser.LoadUrl
        http status code = 0
    [wxpython.py] LoadHandler::OnLoadingStateChange()
        isLoading = True, canGoBack = False, canGoForward = False
    [CEF Python] Renderer: DoJavascriptBindingsForFrame(): bindings are set
    [wxpython.py] RequestHandler::OnBeforeBrowse()
        url = file:///home/czarek/cefpython/cefpython/cefpython/cef3/linux/binaries_64bit/example.html
    [CEF Python] Renderer: OnProcessMessageReceived(): DoJavascriptBindings
    [wxpython.py] RequestHandler::OnBeforeResourceLoad()
        url = file:///home/czarek/cefpython/cefpython/cefpython/cef3/linux/binaries_64bit/example.html
    [CEF Python] Renderer: OnContextReleased()
    [CEF Python] Renderer: OnContextCreated()
    [CEF Python] Renderer: DoJavascriptBindingsForFrame(): bindings are set
    [CEF Python] Browser: OnProcessMessageReceived(): OnContextReleased
    [CEF Python] V8ContextHandler_OnContextReleased()
    [CEF Python] del g_pyFrames[3#3]
    [CEF Python] Browser: OnProcessMessageReceived(): RemovePythonCallbacksForFrame
    [CEF Python] Browser: OnProcessMessageReceived(): OnContextCreated
    [CEF Python] V8ContextHandler_OnContextCreated()
    [CEF Python] Renderer: DoJavascriptBindingsForFrame(): bindings are set
    [0730/145552:ERROR_REPORT:v8_impl.cc(910)] Check failed: false. V8 handle is not valid
    [0730/145552:ERROR_REPORT:v8_impl.cc(901)] Check failed: false. V8 handle is not valid
    [0730/145552:ERROR_REPORT:v8_impl.cc(1161)] Check failed: false. not currently in a V8 context
    [wxpython.py] LoadHandler::OnLoadStart()
        frame url = file:///home/czarek/cefpython/cefpython/cefpython/cef3/linux/binaries_64bit/example.html
    [wxpython.py] DisplayHandler::OnAddressChange()
        url = file:///home/czarek/cefpython/cefpython/cefpython/cef3/linux/binaries_64bit/example.html
    [CEF Python] Browser: OnRenderProcessTerminated()
    [wxpython.py] RequestHandler::OnRendererProcessTerminated()
        status = TS_PROCESS_CRASHED
    [wxpython.py] LoadHandler::OnLoadingStateChange()
        isLoading = False, canGoBack = True, canGoForward = False
    [wxpython.py] DisplayHandler::OnTitleChange()
        title = example.html
    [CEF Python] Browser: OnRenderProcessTerminated()
    [wxpython.py] RequestHandler::OnRendererProcessTerminated()
        status = TS_PROCESS_CRASHED
    [CEF Python] del g_pyFrames[3#3]
    [CEF Python] del g_pyBrowsers[3]
    (.:2373): LIBDBUSMENU-GLIB-WARNING **: Trying to remove a child that doesn't believe we're it's parent.
    (.:2373): LIBDBUSMENU-GLIB-WARNING **: Trying to remove a child that doesn't believe we're it's parent.
    [CEF Python] Shutdown()
    [CEF Python] del g_pyFrames[1#1]
    [CEF Python] del g_pyBrowsers[1]
    ./wxpython.sh: line 2:  2373 Segmentation fault      (core dumped) python wxpython.py

Original issue reported on code.google.com by czarek.t...@gmail.com on 30 Jul 2014 at 1:00