[BlackBerry] GraphicsContext3D: implement ImageExtractor::extractImage()
https://bugs.webkit.org/show_bug.cgi?id=112242

Patch by Alberto Garcia <agarcia@igalia.com> on 2013-03-14
Reviewed by Rob Buis.

In r136282 GraphicsContext3D::getImageData() was refactored in a
new class called ImageExtractor.

This patch implements the necessary changes for the BlackBerry
port, which is still using the old API.

* platform/graphics/GraphicsContext3D.h:
(ImageExtractor):
* platform/graphics/blackberry/GraphicsContext3DBlackBerry.cpp:
(WebCore::GraphicsContext3D::ImageExtractor::~ImageExtractor):
(WebCore):
(WebCore::GraphicsContext3D::ImageExtractor::extractImage):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@145814 268f45cc-cd09-0410-ab3c-d52691b4dbfc