Relax representation requirement in FrameStates.

This change enables non-tagged representations in FrameStates.

That allows us to run zlib with deoptimization support and have almost the same performance of the generated code (as the code with no deoptimization). Unfortunately, the frame states seem to confuse typer. As a consequence, we generate more representation changes, which in turn causes the scheduler to take a lot more time and memory (>4x). The added compiler time makes zlib with deopt be about 50% slower.

BUG=
R=titzer@chromium.org

Review URL: https://codereview.chromium.org/614713002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24454 ce2b1a6d-e550-0410-aec6-3dcde31c8c00