Add an apex_contributions_defaults module to module sdk

This metadata module will contain a flattened list of all the soong
modules contributed by this module to the rest of the build. This is
supported in V and above.

Bug: 326246905
Test: m art-module-host-exports
Test: unzip -p out/soong/mainline-sdks/art-module-host-exports-current.zip Android.bp | grep -A 15 apex_contributions_defaults
apex_contributions_defaults {
    name: "art-module-host-exports.contributions",
    contents: [
        "prebuilt_art.module.api.annotations",
        "prebuilt_dex2oat",
        "prebuilt_dex2oatd",
        "prebuilt_dexdump",
        "prebuilt_hiddenapi",
        "prebuilt_oatdump",
        "prebuilt_profman",
        "prebuilt_veridex",
        "prebuilt_libartpalette",
        "prebuilt_libartbase",
    ],
}

Change-Id: Iba43a9da5430adfc0a5fd9b5dc27b5d89c5eacb8
diff --git a/sdk/sdk_test.go b/sdk/sdk_test.go
index c4df146..f9d49d9 100644
--- a/sdk/sdk_test.go
+++ b/sdk/sdk_test.go
@@ -118,6 +118,16 @@
 		checkAndroidBpContents(`
 // This is auto-generated. DO NOT EDIT.
 
+apex_contributions_defaults {
+    name: "mysdk.contributions",
+    contents: [
+        "prebuilt_myjavalib",
+        "prebuilt_mypublicjavalib",
+        "prebuilt_mydefaultedjavalib",
+        "prebuilt_myprivatejavalib",
+    ],
+}
+
 java_import {
     name: "myjavalib",
     prefer: false,
@@ -398,6 +408,11 @@
 			checkAndroidBpContents(`
 // This is auto-generated. DO NOT EDIT.
 
+apex_contributions_defaults {
+    name: "mysdk.contributions",
+    contents: ["prebuilt_myjavalib"],
+}
+
 java_import {
     name: "myjavalib",
     prefer: false,
@@ -453,6 +468,11 @@
 			checkAndroidBpContents(`
 // This is auto-generated. DO NOT EDIT.
 
+apex_contributions_defaults {
+    name: "mysdk.contributions",
+    contents: ["prebuilt_mysdklibrary"],
+}
+
 prebuilt_bootclasspath_fragment {
     name: "mybootclasspathfragment",
     prefer: false,