Implement non-generic stores for object literals.

Implement non-generic stores for object literals.

This uses the type feedback already present for computed value stores
into object literals to generate optimized stores in Crankshaft, thus
avoiding unnecessary generic stores with side effects.

R=svenpanne@chromium.org

Review URL: https://chromiumcodereview.appspot.com/9692036

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11023 ce2b1a6d-e550-0410-aec6-3dcde31c8c00