Do not replace the direct edge between rdeps and java_sdk_library

android/prebuilt.go#isSelected has a special-case inside it to ignore
apex_contributions contents for the top-level java_sdk_library hook.
This was necessary because even though we might want source stubs in
next builds, we still needed the top-level prebuilt hook to be active to
emit the dexpreopt rules to .mk.

This worked fine for rdeps that create a dependency edge on the child
stub modules of java_sdk_library. Notable examples include the full
android api stubs created by f/b/api.go. In postdeps mutator, these
expanded deps get rewritten to source/prebuilt if necesssry.

The exception to this are workflows which depend on the top-level hook
directly via `libs`. We resolve these rdeps to an appropriate provider
during GenerateAndroidBuildActions stage. This meant that rdeps were
getting prebuilt stubs of these even in next builds.

Bug: 323454855

Test: Added a unit test

Test: lunch cf_x86_64_only_phone-next-userdebug
Test: aninja -t query
out/soong/.intermediates/packages/modules/Permission/SafetyCenter/Config/safety-center-config/android_common/javac/safety-center-config.jar
| grep prebilts/module_sdk # empty now

Change-Id: Id91333d88055519f3c58ab40466f9628085f5180

android/prebuilt.go

@@ -547,13 +547,29 @@ func PrebuiltPostDepsMutator(ctx BottomUpMutatorContext) {
 	if p := GetEmbeddedPrebuilt(m); p != nil {
 		bmn, _ := m.(baseModuleName)
 		name := bmn.BaseModuleName()
+		psi := PrebuiltSelectionInfoMap{}
+		ctx.VisitDirectDepsWithTag(acDepTag, func(am Module) {
+			psi, _ = OtherModuleProvider(ctx, am, PrebuiltSelectionInfoProvider)
+		})
+
 		if p.properties.UsePrebuilt {
 			if p.properties.SourceExists {
 				ctx.ReplaceDependenciesIf(name, func(from blueprint.Module, tag blueprint.DependencyTag, to blueprint.Module) bool {
+					if sdkLibrary, ok := m.(interface{ SdkLibraryName() *string }); ok && sdkLibrary.SdkLibraryName() != nil {
+						// Do not replace deps to the top-level prebuilt java_sdk_library hook.
+						// This hook has been special-cased in #isSelected to be _always_ active, even in next builds
+						// for dexpreopt and hiddenapi processing.
+						// If we do not special-case this here, rdeps referring to a java_sdk_library in next builds via libs
+						// will get prebuilt stubs
+						// TODO (b/308187268): Remove this after the apexes have been added to apex_contributions
+						if psi.IsSelected(*sdkLibrary.SdkLibraryName()) {
+							return false
+						}
+					}
+
 					if t, ok := tag.(ReplaceSourceWithPrebuilt); ok {
 						return t.ReplaceSourceWithPrebuilt()
 					}
-
 					return true
 				})
 			}
@@ -584,6 +600,7 @@ func isSelected(psi PrebuiltSelectionInfoMap, m Module) bool {
 		sln := proptools.String(sdkLibrary.SdkLibraryName())
 		// This is the top-level library
 		// Do not supersede the existing prebuilts vs source selection mechanisms
+		// TODO (b/308187268): Remove this after the apexes have been added to apex_contributions
 		if sln == m.base().BaseModuleName() {
 			return false
 		}

java/sdk_library_test.go

@@ -1772,3 +1772,61 @@ func TestSdkLibraryExportableStubsLibrary(t *testing.T) {
 		"top level exportable stubs library", []string{exportableSourceStubsLibraryModuleName},
 		topLevelModule.Module().(*Library).properties.Static_libs)
 }
+
+// For java libraries depending on java_sdk_library(_import) via libs, assert that
+// rdep gets stubs of source if source is listed in apex_contributions and prebuilt has prefer (legacy mechanism)
+func TestStubResolutionOfJavaSdkLibraryInLibs(t *testing.T) {
+	bp := `
+		apex_contributions {
+			name: "my_mainline_module_contributions",
+			api_domain: "my_mainline_module",
+			contents: ["sdklib"], // source is selected using apex_contributions, but prebuilt is selected using prefer
+		}
+		java_sdk_library {
+			name: "sdklib",
+			srcs: ["a.java"],
+			sdk_version: "none",
+			system_modules: "none",
+			public: {
+				enabled: true,
+			},
+		}
+		java_sdk_library_import {
+			name: "sdklib",
+			public: {
+				jars: ["a.jar"],
+				stub_srcs: ["a.java"],
+				current_api: "current.txt",
+				removed_api: "removed.txt",
+				annotations: "annotations.zip",
+			},
+			prefer: true, // Set prefer explicitly on the prebuilt. We will assert that rdep gets source in a test case.
+		}
+		// rdeps
+		java_library {
+			name: "mymodule",
+			srcs: ["a.java"],
+			sdk_version: "current",
+			libs: ["sdklib",], // this should be dynamically resolved to sdklib.stubs (source) or prebuilt_sdklib.stubs (prebuilt)
+		}
+	`
+
+	fixture := android.GroupFixturePreparers(
+		prepareForJavaTest,
+		PrepareForTestWithJavaSdkLibraryFiles,
+		FixtureWithLastReleaseApis("sdklib"),
+		android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
+			variables.BuildFlags = map[string]string{
+				// We can use any of the apex contribution build flags from build/soong/android/config.go#mainlineApexContributionBuildFlags here
+				"RELEASE_APEX_CONTRIBUTIONS_ADSERVICES": "my_mainline_module_contributions",
+			}
+		}),
+	)
+
+	result := fixture.RunTestWithBp(t, bp)
+	// Make sure that rdeps get the correct source vs prebuilt based on mainline_module_contributions
+	public := result.ModuleForTests("mymodule", "android_common")
+	rule := public.Output("javac/mymodule.jar")
+	inputs := rule.Implicits.Strings()
+	android.AssertStringListContains(t, "Could not find the expected stub on classpath", inputs, "out/soong/.intermediates/sdklib.stubs/android_common/turbine-combined/sdklib.stubs.jar")
+}