[Texmap] TextureMapperGL should reset ARRAY_BUFFER after painting.
https://bugs.webkit.org/show_bug.cgi?id=106098

This fixes the issue of the address bar disappearing in
Qt/MiniBrowser after r138555.

Reviewed by Jocelyn Turcotte.

* platform/graphics/texmap/TextureMapperGL.cpp:
(WebCore::TextureMapperGL::drawEdgeTriangles):
(WebCore::TextureMapperGL::drawUnitRect):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@138891 268f45cc-cd09-0410-ab3c-d52691b4dbfc