ES6: Make Map/Set constructors support iterable values

Same for WeakMap/WeakSet

https://bugs.ecmascript.org/show_bug.cgi?id=3111

The change from the reverted version is that LoadIC_Miss now uses Name
instead of String.

BUG=v8:3508
LOG=Y
R=adamk@chromium.org, dslomov@chromium.org

Review URL: https://codereview.chromium.org/464093002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23108 ce2b1a6d-e550-0410-aec6-3dcde31c8c00