Add apex.use_vndk_as_stable property

Vendor APEXes(in general, APEXes for non-system partitions) which is
supposed to be tied to a specific VNDK version can set this new property
so that it excludes VNDK libs and use them from VNDK APEX (provided by
system parition).

For these APEXes to use VNDK libs from VNDK APEX, linkerconfig should
link "vndk" linker namespace to the namespaces of these APEXes.

Bug: 159195575
Test: m (soong test added)
Change-Id: If90650973239ef7aab0ff084488bda57d9b0364e

apex/apex_test.go

@@ -2203,6 +2203,55 @@ func TestVendorApex(t *testing.T) {
 	ensureContains(t, androidMk, `LOCAL_MODULE_PATH := /tmp/target/product/test_device/vendor/apex`)
 }
 
+func TestVendorApex_use_vndk_as_stable(t *testing.T) {
+	ctx, _ := testApex(t, `
+		apex {
+			name: "myapex",
+			key: "myapex.key",
+			binaries: ["mybin"],
+			vendor: true,
+			use_vndk_as_stable: true,
+		}
+		apex_key {
+			name: "myapex.key",
+			public_key: "testkey.avbpubkey",
+			private_key: "testkey.pem",
+		}
+		cc_binary {
+			name: "mybin",
+			vendor: true,
+			shared_libs: ["libvndk", "libvendor"],
+		}
+		cc_library {
+			name: "libvndk",
+			vndk: {
+				enabled: true,
+			},
+			vendor_available: true,
+		}
+		cc_library {
+			name: "libvendor",
+			vendor: true,
+		}
+	`)
+
+	vendorVariant := "android_vendor.VER_arm64_armv8-a"
+
+	ldRule := ctx.ModuleForTests("mybin", vendorVariant+"_myapex").Rule("ld")
+	libs := names(ldRule.Args["libFlags"])
+	// VNDK libs(libvndk/libc++) as they are
+	ensureListContains(t, libs, buildDir+"/.intermediates/libvndk/"+vendorVariant+"_shared/libvndk.so")
+	ensureListContains(t, libs, buildDir+"/.intermediates/libc++/"+vendorVariant+"_shared/libc++.so")
+	// non-stable Vendor libs as APEX variants
+	ensureListContains(t, libs, buildDir+"/.intermediates/libvendor/"+vendorVariant+"_shared_myapex/libvendor.so")
+
+	// VNDK libs are not included when use_vndk_as_stable: true
+	ensureExactContents(t, ctx, "myapex", "android_common_myapex_image", []string{
+		"bin/mybin",
+		"lib64/libvendor.so",
+	})
+}
+
 func TestAndroidMk_UseVendorRequired(t *testing.T) {
 	ctx, config := testApex(t, `
 		apex {