Fix representation of Phis for mutable-heapnumber-in-object-literal properties

BUG=v8:3392
LOG=y
R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/328343004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21850 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Reuse AstValueFactory when optimizing.

HOptimizedGraphBuilder::TryInline creates a temporary CompilationInfo and
destroys it, but we don't want the AstValueFactory to be destroyed at the same
time. Reuse the upper CompilationInfo's AstValueFactory.

BUG=
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/334173003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21851 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Merge remote-tracking branch 'upstream/master'