"Fill in" option in graph doesn't work with "VDEF" DEF type

[sizeur]

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BUG REPORT INFORMATION

Centreon Web version:
2.8.9
Centreon Engine version:
1.7.2
Centreon Broker version:
3.0.7
OS:
Centreon 3.4

Steps to reproduce the issue:

1. Create a virtual metric with the option "Hidden Graph And Legend" and with a DEF Type "VDEF":
   

2. Create a second virtual metric CDEF based on the first one:
   

3. Create a new template curve which used the second virtual metric and disable the option "Filling"
   

4. Go to Monitoring > Performances > Graphs

Describe the results you received:
The curve is always "filled in", when ever the option is enabled or not:

Describe the results you expected:

The option "Fill in" should be taken into account

[thiuyendang]

Tested in 2.8.10, CentOS6, CentOS7 : OK