Handle retry-after-gc failures within KeyedLoadIC::Load and KeyedStoreIC::Store.

Handle retry-after-gc failures within KeyedLoadIC::Load and KeyedStoreIC::Store.

Returning retry-after-gc failure from these functions causes them to be
re-executed after ic state change, which breaks stub computation assumptions.

R=verwaest@chromium.org
BUG=222301
TEST=mjsunit/array-bounds-check-removal.js --gc_interval=10 in x64.debug

[ulan, 2013-04-15 16:17:05]

Please take a look.

Once we agree on naming, I will add handling of more functions in LoadIC and
StoreIC in a separate CL:

Accessors::FunctionGetPrototype,
Runtime::GetElementOrCharAt,
Object::GetProperty,
JSProxy::SetProperty,
JSObject::SetProperty.

[Toon Verwaest, 2013-04-16 12:13:24]

LGTM. Missing support for indexed properties (and perhaps calls), but as
discussed offline, it's fine to land that in a separate CL.