[indylambda] Support lambda {de}serialization

To support serialization, we use the alternative lambda metafactory
that lets us specify that our anonymous functions should extend the
marker interface `scala.Serializable`. They will also have a
`writeObject` method added that implements the serialization proxy
pattern using `j.l.invoke.SerializedLamba`.

To support deserialization, we synthesize a `$deserializeLamba$`
method in each class with lambdas. This will be called reflectively by
`SerializedLambda#readResolve`. This method in turn delegates to
`LambdaDeserializer`, currently defined [1] in `scala-java8-compat`,
that uses `LambdaMetafactory` to spin up the anonymous class and
instantiate it with the deserialized environment.

Note: `LambdaDeserializer` can reuses the anonymous class on subsequent
deserializations of a given lambda, in the same spirit as an
invokedynamic call site only spins up the class on the first time
it is run. But first we'll need to host a cache in a static field
of each lambda hosting class. This is noted as a TODO and a failing
test, and will be updated in the next commit.

`LambdaDeserializer` will be moved into our standard library in
the 2.12.x branch, where we can introduce dependencies on the
Java 8 standard library.

The enclosed test cases must be manually run with indylambda enabled.
Once we enable indylambda by default on 2.12.x, the test will
actually test the new feature.

```
% echo $INDYLAMBDA
-Ydelambdafy:method -Ybackend:GenBCode -target:jvm-1.8 -classpath .:scala-java8-compat_2.11-0.5.0-SNAPSHOT.jar
% qscala $INDYLAMBDA -e "println((() => 42).getClass)"
class Main$$anon$1$$Lambda$1/1183231938
% qscala $INDYLAMBDA -e "assert(classOf[scala.Serializable].isInstance(() => 42))"
% qscalac $INDYLAMBDA test/files/run/lambda-serialization.scala && qscala $INDYLAMBDA Test
```

This commit contains a few minor refactorings to the code that
generates the invokedynamic instruction to use more meaningful
names and to reuse Java signature generation code in ASM rather
than the DIY approach.

[1] https://github.com/scala/scala-java8-compat/pull/37

1 files changed, 1 insertions, 0 deletions

diff --git a/src/reflect/scala/reflect/runtime/JavaUniverseForce.scala b/src/reflect/scala/reflect/runtime/JavaUniverseForce.scala
index 1c0aa7cf6d..8c03ee7ca3 100644
--- a/src/reflect/scala/reflect/runtime/JavaUniverseForce.scala
+++ b/src/reflect/scala/reflect/runtime/JavaUniverseForce.scala
@@ -310,6 +310,7 @@ trait JavaUniverseForce { self: runtime.JavaUniverse  =>
     definitions.QuasiquoteClass_api_unapply
     definitions.ScalaSignatureAnnotation
     definitions.ScalaLongSignatureAnnotation
+    definitions.LambdaMetaFactory
     definitions.MethodHandle
     definitions.OptionClass
     definitions.OptionModule