Add support for NDK r13.

Test: make checkbuild
Bug: None
Change-Id: I6e7c92d6731be4ae47c7dc5e9444af08d338334b
diff --git a/cc/library.go b/cc/library.go
index 14ceb28..ad1822d 100644
--- a/cc/library.go
+++ b/cc/library.go
@@ -395,6 +395,25 @@
 	sharedLibs := deps.SharedLibs
 	sharedLibs = append(sharedLibs, deps.LateSharedLibs...)
 
+	// TODO(danalbert): Clean this up when soong supports prebuilts.
+	if strings.HasPrefix(ctx.selectedStl(), "ndk_libc++") {
+		libDir := getNdkStlLibDir(ctx, flags.Toolchain, "libc++")
+
+		if strings.HasSuffix(ctx.selectedStl(), "_shared") {
+			deps.StaticLibs = append(deps.StaticLibs,
+				libDir.Join(ctx, "libandroid_support.a"))
+		} else {
+			deps.StaticLibs = append(deps.StaticLibs,
+				libDir.Join(ctx, "libc++abi.a"),
+				libDir.Join(ctx, "libandroid_support.a"))
+		}
+
+		if ctx.Arch().ArchType == android.Arm {
+			deps.StaticLibs = append(deps.StaticLibs,
+				libDir.Join(ctx, "libunwind.a"))
+		}
+	}
+
 	TransformObjToDynamicBinary(ctx, objFiles, sharedLibs,
 		deps.StaticLibs, deps.LateStaticLibs, deps.WholeStaticLibs,
 		linkerDeps, deps.CrtBegin, deps.CrtEnd, false, builderFlags, outputFile)