Enable hiddenapi check for exportable stubs

This change modifies the dependencies of the hiddenapi to always depend
on the exportable stubs, instead of the currently utilized everything
stubs.

To support this, the full api surface exportable stubs are defined in a
separate change at the `frameworks/base` project. Note that the full api
surface exportable stubs are only used for the hiddenapi purpose, and
`sdk_version` continues to utilize the currently existing everything
stubs.

Currently, this feature is hidden behind the build flag
"RELEASE_HIDDEN_API_EXPORTABLE_STUBS". This feature will be fully
enabled once metalava fully supports handling of the flagged apis.

Test: ENABLE_HIDDENAPI_FLAGS=true m
Bug: 317426356
Change-Id: I109b7cd27b20ceffcdf1766ab8106b0c276be2b3
diff --git a/apex/platform_bootclasspath_test.go b/apex/platform_bootclasspath_test.go
index 01b616b..161941d 100644
--- a/apex/platform_bootclasspath_test.go
+++ b/apex/platform_bootclasspath_test.go
@@ -252,6 +252,11 @@
 		java.FixtureWithLastReleaseApis("foo"),
 		java.PrepareForTestWithDexpreopt,
 		dexpreopt.FixtureDisableDexpreoptBootImages(false),
+		android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
+			variables.BuildFlags = map[string]string{
+				"RELEASE_HIDDEN_API_EXPORTABLE_STUBS": "true",
+			}
+		}),
 	).RunTestWithBp(t, `
 		apex {
 			name: "com.android.art",
@@ -386,10 +391,10 @@
 		`platform:all_apex_contributions`,
 
 		// The following are stubs.
-		`platform:android_stubs_current`,
-		`platform:android_system_stubs_current`,
-		`platform:android_test_stubs_current`,
-		`platform:legacy.core.platform.api.stubs`,
+		`platform:android_stubs_current_exportable`,
+		`platform:android_system_stubs_current_exportable`,
+		`platform:android_test_stubs_current_exportable`,
+		`platform:legacy.core.platform.api.stubs.exportable`,
 
 		// Needed for generating the boot image.
 		`platform:dex2oatd`,
@@ -422,6 +427,9 @@
 		java.PrepareForTestWithJavaSdkLibraryFiles,
 		android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
 			variables.Always_use_prebuilt_sdks = proptools.BoolPtr(true)
+			variables.BuildFlags = map[string]string{
+				"RELEASE_HIDDEN_API_EXPORTABLE_STUBS": "true",
+			}
 		}),
 		java.FixtureWithPrebuiltApis(map[string][]string{
 			"current": {},
@@ -546,7 +554,7 @@
 		"platform:prebuilt_sdk_test_current_android",
 
 		// Not a prebuilt as no prebuilt existed when it was added.
-		"platform:legacy.core.platform.api.stubs",
+		"platform:legacy.core.platform.api.stubs.exportable",
 
 		// The platform_bootclasspath intentionally adds dependencies on both source and prebuilt
 		// modules when available as it does not know which one will be preferred.