[birt-dev]CheckIn: Fix Bugzilla Bug 143644 --- Error message is not stra

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

Title: [birt-dev]CheckIn: Fix Bugzilla Bug 143644 --- Error message is not straightforward for incompatible value

- Summary:
Throw out DTE exception while can't find the _expression_.

- Bugzilla Bug (s) Resolved:
Fix Bugzilla Bug 143644 --- Error message is not  straightforward for incompatible value

- Description:
Old code hold DTE exception while only throw the not found exception.
Now Throw out DTE exception while can't find the _expression_.

- 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/data/dte/NativeRowObject.java"

- Files Added:

- Files Deleted

-Wei Zhao