Separate MEGAMORPHIC and GENERIC ic states

Review URL: https://chromiumcodereview.appspot.com/11824063

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@13402 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Add missing VMState(EXTERNAL) for DOM GC callbacks

BUG=

Review URL: https://chromiumcodereview.appspot.com/11958011
Patch from Kentaro Hara <haraken@chromium.org>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@13403 ce2b1a6d-e550-0410-aec6-3dcde31c8c00