rendercontext: Fix border window's painting to work well with rendercontext.
rendercontext: Fix border window's painting to work well with rendercontext.

This partially fixes rendering of comboboxes.

Change-Id: I243f63a0cd83bb435876d3954a073df0acd54c58

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core