[birt-dev]CheckIn: Fix Bugzilla Bug 186285 --- [Automation][Smoke][Regre

["Wei Zhao \(Shang\)" <wei.zhao@xxxxxxxxxxx>]

Title: [birt-dev]CheckIn: Fix Bugzilla Bug 186285 --- [Automation][Smoke][Regression] map and highlight did not work properly

- Summary:
We should not set null value as groupName to cloumn binding.

- Bugzilla Bug (s) Resolved:
Fix Bugzilla Bug 186285 --- [Automation][Smoke][Regression] map and highlight did not work properly

- Description:
We should not set null value as groupName to cloumn binding.

- Tests Description  :
Manual Test.

- Notes to Build Team:

- Notes to Developers:

- Notes to QA:  
 
- Notes to Documentation:  

- Files Edited:
"/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/adapter/ExpressionUtil.java"

- Files Added:

- Files Deleted

-Wei Zhao(Shanghai)