Minor compiler pipeline refactoring. Inline UpdateSharedFunctionInfo and make Parser::Parse responsible for setting the strict mode of the CompilationInfo.

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/555553003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24001 ce2b1a6d-e550-0410-aec6-3dcde31c8c00