Retain all stubs versions in the snapshot.

This is a quick fix to avoid build failures due to prebuilts lacking
stubs versions that the sources have, which causes dependencies on
older version stubs fail on master-art-host where the sources of e.g.
Bionic are no longer available.

More work is required to make the version handling of stubs DTRT - a
TODO comment outlines it.

Test: m nothing
Test: `m runtime-module-sdk`, check that the generated Android.bp
  has the full stubs.versions list like the sources.
Bug: 169373910
Change-Id: I0ebfaf94f9d45a0e58d9785c40e7cea626f0ab83

cc/library_sdk_member.go

@@ -295,9 +295,9 @@ func addPossiblyArchSpecificProperties(sdkModuleContext android.ModuleContext, b
 		outputProperties.AddProperty(property, includeDirs[property])
 	}
 
-	if len(libInfo.StubsVersion) > 0 {
+	if len(libInfo.StubsVersions) > 0 {
 		stubsSet := outputProperties.AddPropertySet("stubs")
-		stubsSet.AddProperty("versions", []string{libInfo.StubsVersion})
+		stubsSet.AddProperty("versions", libInfo.StubsVersions)
 	}
 }
 
@@ -368,10 +368,10 @@ type nativeLibInfoProperties struct {
 	// The specific stubs version for the lib variant, or empty string if stubs
 	// are not in use.
 	//
-	// Marked 'ignored-on-host' as the StubsVersion() from which this is initialized is
+	// Marked 'ignored-on-host' as the AllStubsVersions() from which this is
-	// not set on host and the stubs.versions property which this is written to is does
+	// initialized is not set on host and the stubs.versions property which this
-	// not vary by arch so cannot be android specific.
+	// is written to does not vary by arch so cannot be android specific.
-	StubsVersion string `sdk:"ignored-on-host"`
+	StubsVersions []string `sdk:"ignored-on-host"`
 
 	// Value of SanitizeProperties.Sanitize.Never. Needs to be propagated for CRT objects.
 	SanitizeNever bool `android:"arch_variant"`
@@ -420,7 +420,11 @@ func (p *nativeLibInfoProperties) PopulateFromVariant(ctx android.SdkMemberConte
 	p.exportedGeneratedHeaders = ccModule.ExportedGeneratedHeaders()
 
 	if ccModule.HasStubsVariants() {
-		p.StubsVersion = ccModule.StubsVersion()
+		// TODO(b/169373910): 1. Only output the specific version (from
+		// ccModule.StubsVersion()) if the module is versioned. 2. Ensure that all
+		// the versioned stub libs are retained in the prebuilt tree; currently only
+		// the stub corresponding to ccModule.StubsVersion() is.
+		p.StubsVersions = ccModule.AllStubsVersions()
 	}
 
 	if ccModule.sanitize != nil && proptools.Bool(ccModule.sanitize.Properties.Sanitize.Never) {

sdk/cc_sdk_test.go

@@ -2330,7 +2330,11 @@ cc_prebuilt_library_shared {
     installable: false,
     compile_multilib: "both",
     stubs: {
-        versions: ["3"],
+        versions: [
+            "1",
+            "2",
+            "3",
+        ],
     },
     arch: {
         arm64: {
@@ -2347,7 +2351,11 @@ cc_prebuilt_library_shared {
     prefer: false,
     compile_multilib: "both",
     stubs: {
-        versions: ["3"],
+        versions: [
+            "1",
+            "2",
+            "3",
+        ],
     },
     arch: {
         arm64: {
@@ -2401,7 +2409,11 @@ cc_prebuilt_library_shared {
     installable: false,
     compile_multilib: "both",
     stubs: {
-        versions: ["3"],
+        versions: [
+            "1",
+            "2",
+            "3",
+        ],
     },
     target: {
         host: {
@@ -2431,7 +2443,11 @@ cc_prebuilt_library_shared {
     host_supported: true,
     compile_multilib: "both",
     stubs: {
-        versions: ["3"],
+        versions: [
+            "1",
+            "2",
+            "3",
+        ],
     },
     target: {
         host: {