[Qt][WK1] Support WebGL with EGL on Linux

https://bugs.webkit.org/show_bug.cgi?id=118251

Reviewed by Kenneth Rohde Christiansen.

Source/WebCore:

Let GraphicsContext3D work without a GraphicsSurface.

* Target.pri:
* platform/graphics/OpenGLShims.cpp:
(WebCore::getProcAddress):
* platform/graphics/qt/GraphicsContext3DQt.cpp:
(WebCore::GraphicsContext3DPrivate::GraphicsContext3DPrivate):
(WebCore::GraphicsContext3DPrivate::paintToTextureMapper):

Tools:

* qmake/mkspecs/features/features.prf:

Change-Id: I6b126c9e6cd01c0db508a63166bc3c66e80f64fc
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@152282 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>
[Qt][WK1] Support direct painting without GraphicsSurface

https://bugs.webkit.org/show_bug.cgi?id=118302

Reviewed by Jocelyn Turcotte.

Configure the WebGL OpenGL context to share texture with
the HostWindow OpenGL if available, and paint accelerated
using the the now shared textures.

This should return the performance without GraphicsSurface
on the WK1 code path to what it was before r135995 (28/11 2012).

* platform/graphics/qt/GraphicsContext3DQt.cpp:
(WebCore::GraphicsContext3DPrivate::GraphicsContext3DPrivate):
(WebCore::GraphicsContext3DPrivate::paintToTextureMapper):

Change-Id: I3b2cdf2d06702c18b21a62eed0f6821d08033ec7
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@152969 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>