QtWebEngine issue

Hi Neel,

Per our earlier discussion on the QtWebEngine crash we were seeing,
here's some more info from my testing.

I turned off high performance graphics in VMware, and started to get
almost immediate crashes of the runtime (from which I could get little
useful information)

With:

QCoreApplication::setAttribute(Qt::AA_UseSoftwareOpenGL);

I managed to get it to run again, but then I commented that back out,
and it was still running without immediately crashing. The black
screen issue is still occurring though, albeit with various errors
that may or may not be given with each crash:

I often see lots of this message:

context mismatch in svga_sampler_view_destroy

I have seen this a few times:

[1109/153107:ERROR:scoped_ole_initializer.cc(20)] Multiple
OleInitialize() calls for thread 5644
[1109/153107:ERROR:scoped_ole_initializer.cc(20)] Multiple
OleInitialize() calls for thread 5644

I have seen this more rarely (on occasions where it occurs before the
black screen of death):

2016-11-09 15:38:39,917: INFO werkzeug: 127.0.0.1 - - [09/Nov/2016
15:38:39] "GET /sqleditor/poll/9539586 HTTP/1.1" 500 -
Traceback (most recent call last):
  File "C:\Program Files\PostgreSQL\9.6\pgAdmin
4\venv\Lib\site-packages\flask\app.py", line 2000, in __call__
    return self.wsgi_app(environ, start_response)
  File "C:\Program Files\PostgreSQL\9.6\pgAdmin
4\venv\Lib\site-packages\flask\app.py", line 1984, in wsgi_app
    ctx.push()
  File "C:\Program Files\PostgreSQL\9.6\pgAdmin
4\venv\Lib\site-packages\flask\ctx.py", line 332, in push
    self.session = self.app.open_session(self.request)
  File "C:\Program Files\PostgreSQL\9.6\pgAdmin
4\venv\Lib\site-packages\flask\app.py", line 914, in open_session
    return self.session_interface.open_session(self, request)
  File "C:\Users\dpage\Documents\pgadmin4\web\pgadmin\utils\session.py",
line 249, in open_session
    return self.manager.get(sid, digest)
  File "C:\Users\dpage\Documents\pgadmin4\web\pgadmin\utils\session.py",
line 133, in get
    del self._cache[sid]
  File "C:\Python27\Lib\collections.py", line 86, in __delitem__
    link_prev, link_next, _ = self.__map.pop(key)
KeyError: u'84c7ee6c-6ab7-4c52-a5b7-45d6c9f7e87d'

Finally, I've seen this a couple of times:

context mismatch in svga_sampler_view_destroy
[1109/153857:FATAL:resource_scheduler.cc(1051)] Check failed:
client_map_.empty().
Backtrace:
GetHandleVerifier [0x11C47DD1+23425]
IsSandboxedProcess [0x11BD464B+6479819]
QtWebEngineCore::BrowserContextAdapter::isOffTheRecord [0x108C0B06+1858950]
QtWebEngineCore::BrowserContextAdapter::isOffTheRecord [0x1072EC46+212678]
QtWebEngineCore::BrowserContextAdapter::isOffTheRecord [0x1072E886+211718]
QtWebEngineCore::BrowserContextAdapter::isOffTheRecord [0x107434D9+296793]
QtWebEngineCore::BrowserContextAdapter::isOffTheRecord [0x1074334A+296394]
QtWebEngineCore::BrowserContextAdapter::isOffTheRecord [0x10737FBD+250429]
IsSandboxedProcess [0x119E5501+4451969]
CertificateErrorController::error [0x10C83E6A+1234282]
QtWebEngineCore::BrowserContextAdapter::isOffTheRecord [0x109CC7BC+2955836]
IsSandboxedProcess [0x1198397F+4051711]
GetHandleVerifier [0x11CB3E0B+465851]
IsSandboxedProcess [0x11BFF020+6654368]
IsSandboxedProcess [0x11BFD494+6647316]
IsSandboxedProcess [0x11BFD9DD+6648669]
GetHandleVerifier [0x11CB68B2+476770]
GetHandleVerifier [0x11CB8312+483522]
GetHandleVerifier [0x11CB827C+483372]
IsSandboxedProcess [0x11BFED0F+6653583]
IsSandboxedProcess [0x11C18286+6757382]
IsSandboxedProcess [0x11BFEB8D+6653197]
IsSandboxedProcess [0x11C313E6+6860134]
QtWebEngineCore::JavaScriptDialogController::qt_static_metacall
[0x106BCEA4+5221044]
QtWebEngineCore::JavaScriptDialogController::qt_static_metacall
[0x106BDFE8+5225464]
IsSandboxedProcess [0x11C31F78+6863096]
IsSandboxedProcess [0x11C384D3+6889043]
BaseThreadInitThunk [0x750E95E4+36]
RtlCheckPortableOperatingSystem [0x7744241A+362]
RtlCheckPortableOperatingSystem [0x774423E9+313]

--
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake

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