Sort bag by attribute key when using libs

When shared libraries are assigned package ids in a different order
than compile order, bag resources that use attributes from both
multiple libraries will not be sorted in ascending attribute id order.
This change detects when the attribute ids are not in order and sorts
the bag entries accordingly.

The change is designed to be less invasive. Deduping the GetBag logic
should probably be spun off in a separate bug.

Bug: 147674078
Test: libandroidfw_tests
Change-Id: Id8ce8e9c7ef294fcc312b77468136067d392dbd0
diff --git a/libs/androidfw/tests/AssetManager2_test.cpp b/libs/androidfw/tests/AssetManager2_test.cpp
index 2f6f3df..35fea7a 100644
--- a/libs/androidfw/tests/AssetManager2_test.cpp
+++ b/libs/androidfw/tests/AssetManager2_test.cpp
@@ -285,6 +285,27 @@
   EXPECT_EQ(0x03, get_package_id(bag->entries[1].key));
 }
 
+TEST_F(AssetManager2Test, FindsBagResourceFromMultipleSharedLibraries) {
+  AssetManager2 assetmanager;
+
+  // libclient is built with lib_one and then lib_two in order.
+  // Reverse the order to test that proper package ID re-assignment is happening.
+  assetmanager.SetApkAssets(
+      {lib_two_assets_.get(), lib_one_assets_.get(), libclient_assets_.get()});
+
+  const ResolvedBag* bag = assetmanager.GetBag(libclient::R::style::ThemeMultiLib);
+  ASSERT_NE(nullptr, bag);
+  ASSERT_EQ(bag->entry_count, 2u);
+
+  // First attribute comes from lib_two.
+  EXPECT_EQ(2, bag->entries[0].cookie);
+  EXPECT_EQ(0x02, get_package_id(bag->entries[0].key));
+
+  // The next two attributes come from lib_one.
+  EXPECT_EQ(2, bag->entries[1].cookie);
+  EXPECT_EQ(0x03, get_package_id(bag->entries[1].key));
+}
+
 TEST_F(AssetManager2Test, FindsStyleResourceWithParentFromSharedLibrary) {
   AssetManager2 assetmanager;