A64: Tidy up a couple of TODOs.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/189883006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@19809 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fix kraken/oscillator performance regression after r19635.

Evict previously optimized code after new optimization.

BUG=v8:3202
LOG=N
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/189263009

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@19810 ce2b1a6d-e550-0410-aec6-3dcde31c8c00