Code Refactor: Remove getActivityStack() from this class.

Signed-off-by: Pengcheng Bian <pbian@actuate.com>
Fix 456310 Change Report item names and support pdf feature.
Code Refactor. Fix broken features.
Code Refactor, fix broken feature.
Code Refactor. Avoid ambiguous report item names. 

Signed-off-by: Pengcheng Bian <pbian@actuate.com>
Merge pull request #53 from TerryPCBian/master

Code Refactor: Remove getActivityStack() from this class.