The least two bits of the owner field of a Page are used to determine
whether the Page is part of a large object. If these bits are not equal
to 0x11, the page is part of a large object and needs special handling
e.g. in MemoryChunk::FromAnyPointerAddress to determine which chunk it
belongs to.

This CL fixes an issue in which the store buffer overflows after
a large object space allocation but before the object has been fully
initialized. Store buffer overflow handling attempts to look up the
chunk of a page, but fails to do so correctly since the page's owner
field has not yet been initialized.

This CL ensures that the owner field of all pages belonging to a large
object allocation are initialized to a value that is interpreted
correctly.

BUG=chromium:672041

Committed: https://crrev.com/9b6808bfb5366beebe3af30a06f9851edb2039d4
Review-Url: https://codereview.chromium.org/2565713002
Cr-Original-Commit-Position: refs/heads/master@{#41641}
Cr-Commit-Position: refs/heads/master@{#41687}