Can rowHeightGetter get column width while some column use flexGrow

[jany3534]

Expected Behavior

While some column use flexGrow, we can get the actual width of those columns in rowHeightGetter.
So that we can figure out the appropriate row height.

Current Behavior

We don't know the actual width of flexGrow rows.

Possible Solution

Provide all columns' width in parameters of rowHeightGetter.

Steps to Reproduce (for bugs)

Your Environment

• Version used: 0.8.6
• Browser Name and version: Google Chrome 66.0.3359.181
• Operating System and version (desktop or mobile): window 10 desktop

[jany3534]

I can get the rendered table columns‘ width, but it need render twice.

[wcjordan]

I'd be happy to accept a PR for this assuming we can implement it without breaking existing rowHeightGetters.