Merged r19599, r19591 into 3.24 branch.

Fix representation generalization for doubles.

HAllocate should never generate allocation code if the requested size does not fit into page. Regression test included.

BUG=347543
LOG=N
R=hpayer@chromium.org, hpayer@google.com

Review URL: https://codereview.chromium.org/178473013

git-svn-id: https://v8.googlecode.com/svn/branches/3.24@19633 ce2b1a6d-e550-0410-aec6-3dcde31c8c00