Start adding build rules for ravenwood

- Add "framework-minus-apex.ravenwood".
- Update the behavior of: --default-throw:
  - Now this will "keep" the subject classes and fields.
- When a 'throw' directive is specified on a static initializer,
  it's now handled as 'keep', because otherwise the class
  wouldn't be usable.

Test: ./scripts/run-all-tests.sh
Test: m framework-minus-apex.ravenwood
Bug: 292141694
Change-Id: If4d650dc175a5a78cf8844dfed2217c19f2d5790
diff --git a/ravenwood/Android.bp b/ravenwood/Android.bp
new file mode 100644
index 0000000..91acc3d
--- /dev/null
+++ b/ravenwood/Android.bp
@@ -0,0 +1,33 @@
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "frameworks_base_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["frameworks_base_license"],
+}
+
+filegroup {
+    name: "ravenwood-annotations",
+    srcs: [
+        "annotations-src/**/*.java",
+    ],
+    visibility: ["//visibility:public"],
+}
+
+// File that contains the standard command line arguments to hoststubgen.
+filegroup {
+    name: "ravenwood-standard-options",
+    srcs: [
+        "ravenwood-standard-options.txt",
+    ],
+    visibility: ["//visibility:public"],
+}
+
+java_library {
+    name: "ravenwood-annotations-lib",
+    srcs: [":ravenwood-annotations"],
+    sdk_version: "core_current",
+    host_supported: true,
+    visibility: ["//visibility:public"],
+}