Bug 934860 - Start and finish transactions with temporary layer managers each time we use them to ensure that these are paired. r=roc
Bug 934860 - Move some parts of FrameLayerBuilder::DrawThebesLayer into helper functions. r=roc
Bug 934860 - Move paint region clipping into DrawThebesLayer. r=roc
Bug 934860 - Draw each rect of the invalid region separately on Direct2D. r=roc
Bug 934860 - Don't paint display items that don't intersect the current invalid rects. r=roc