Move some Pop/Drop calls directly to the places where they are needed.

Move some Pop/Drop calls directly to the places where they are needed.

This is a refactoring-only CL and the fourth one in a series for enabling
inlining of accessors. Later when we try to inline accessor calls, their
arguments must still be on the expression stack, so we must not remove them too
early.

Review URL: https://chromiumcodereview.appspot.com/10828049

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12213 ce2b1a6d-e550-0410-aec6-3dcde31c8c00