Dramatically simplifies public API of RequestFactory and
ValueStore. Values<> interface and ValuesKey are gone,
replaced by bean-like Record interfaces.

Also eliminates Visitor pattern, falling back on various
instanceof checks.  We'll likely need something like them, but
per-entity seemed wrong and was complicating life on both
sides.

One concern: value store records are still JSOs, but when
client code handles them they are wrapped by a Java
facade. This is in part to work around a bug that prevents
JSOs from being based on asbstract classes, (GWT issue 4859)
and in part to preserve normal Java semantics, particularly
instanceof.

This also enshrines the previously kind of implicit "all ids
are strings once they reach the client" notion. This may need
to be re-visited and relaxed.

Under the hood, what was the ValuesKey is still kind of
around, rechristened Schema. However, it appears only in impl
packages; is used only by GWT-generated code; and is not used
at all server side.

Review at http://gwt-code-reviews.appspot.com/344804

Review by: amitmanjhi@google.com

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@7932 8db76d5a-ed1c-0410-87a9-c151d255dfc7
62 files changed