Improve DicNode handling.

- Stop creating useless DicNode and DicNodeVector.
- Remove useless virtual.
- Implement copy constructor and assignment operator of DicNodeState.
- Remove useless memset.

Before:
(0)  2266.21 (0.79%)
(1)  285422.05 (98.97%)
(2)  642.62 (0.22%)
(66)  0.19 (0.00%)
Total 288384.35 (sum of others 288331.07)

After:
(0)  2232.70 (0.86%)
(1)  255258.50 (98.89%)
(2)  585.73 (0.23%)
(66)  0.26 (0.00%)
Total 258126.46 (sum of others 258077.18)


Change-Id: I0bb1e9de8b38a6743a11aaeb2b17bd0da5b7ad34