CMFileManager: Refresh the disk usage graph when layout size change

The size of disk usage graph was caculated dynamically according to
the parent layout size. When the device was rotated from landscape
to portrait, the layout size was changed, but the disk usage graph
did not refresh.

Redraw the graph when the view size changes.

Change-Id: I2e283ed77f44b759f4f3753ff92fe95d851b6433
CRs-Fixed: 889743