Added highly efficient Object::SetAlignedPointerInInternalField and
Object::GetAlignedPointerFromInternalField functions for 2-byte-aligned
pointers. Their non-aligned counterparts Object::GetPointerFromInternalField and
Object::SetPointerInInternalField are now deprecated utility functions.

External is now a true Value again, with New/Value/Cast using a JSObject with an
internal field containing a Foreign. External::Wrap, and External::Unwrap are now
deprecated utility functions.

Added Context::GetEmbedderData and Context::SetEmbedderData. Deprecated
Context::GetData and Context::SetData, these are now only wrappers to access
internal field 0.

Added highly efficient Context::SetAlignedPointerInEmbedderData and
Context::GetAlignedPointerFromEmbedderData functions for 2-byte-aligned
pointers.

Review URL: https://codereview.chromium.org/11190050

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12849 ce2b1a6d-e550-0410-aec6-3dcde31c8c00