SDK 0.9.6 <js:DataGridPercentageView/> bead work only on header DataGrid, not on cells

Hi,

Let't take this code

```

@namespace js "library://ns.apache.org/royale/basic";

.DataGridColumnList .StringItemRenderer {
border-style: solid;
border-color: #CCCCCC;
border-width: 1px;
background-color: #ffffff;
line-height: 40px;
padding: 2px;
}

.DataGridColumnList .DataItemRenderer {
border-style: solid;
border-color: #CCCCCC;
border-width: 1px;
background-color: #ffffff;
line-height: 40px;
padding: 2px;
}

```

Here is the result


Start by reproducing the provided MXML example with DataGridPercentageView and compare its behavior on the header DataGrid and its cells. Trace the DataGridPercentageView entry point and related DataGrid rendering to determine why the bead affects only the header; done means the percentage behavior also applies to the cells.

Written by the indexing model from the issue text.