improve chart series symbol export

Using the chart2 service allows us to export series symbols instead of
the diagram settings.

Change-Id: Ic46f067b60c972af35c0628b3ec4f7851580d725
remove whitespace

Change-Id: I69454c3d9bddfe01da2622117a16bbb37797062a
import data point symbol color

Change-Id: I27ebd67a535f8617a6f535414ee8426fae6614b9
export data point symbol color

Change-Id: I0dcbf616b8ab3c8cea4437d399fa4b5ec33e475a