Dereference null return value, TimechartTransformation.java

[Abigael-JT]

Describe the bug

visitT_timechart_divideByInstruction returns null
Calling a method on null object visitT_timechart_divideByInstruction

Expected behavior

How to reproduce

Screenshots

Software version

Desktop (please complete the following information if relevant):

• OS:
• Browser:
• Version:

Additional context

Coverity scan : CID 443509

[Abigael-JT]

Waiting for PR #490 to be merged first, might fix the issues