Update GL renderer to fire the correct area changed event (updates to other renderers to follow later)
Update GL renderer to fire the correct area changed event (updates to other renderers to follow later)

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branch : multi-root-devel

cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two,cbeck88/cegui-mirror-two