[Merge] lp:~dandrader/qtubuntu/improve-resize into lp:qtubuntu

[Daniel d'Andrada]

The proposal to merge lp:~dandrader/qtubuntu/improve-resize into lp:qtubuntu has been updated.

Commit Message changed to:

Drastically improve surface resize responsiveness

QWindowSystemInterface::handleFoo() methods are thread safe, thus there's no need to have intermetiate methods between the rendering thread and such calls.

There was also some miscommunication between the now absent handleBufferResize() slot from the main thread and the swapbuffer handler from the render thread.

For more details, see:
https://code.launchpad.net/~dandrader/qtubuntu/improve-resize/+merge/258912
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Your team Ubuntu Phablet Team is requested to review the proposed merge of lp:~dandrader/qtubuntu/improve-resize into lp:qtubuntu.