Copy common resources between styles

The docuemntation of setTo states that the resources two styles from
different AssetManagers have in common will be set in the destination
theme. This change adds this functionality. The package ids of the
attributes, the package ids of reference values, and the cookie of
attribute values have to be rewritten to match the destination
AssetManager. This change can later be made more generic if rewriting
references between packages is needed elsewhere.

Bug: 115897657
Test: libandroidfw_tests and manual test of app specified in the bug
Change-Id: Iee999ea2cc8473168cac11aaf3c34e14c958e5ae
diff --git a/libs/androidfw/tests/Theme_test.cpp b/libs/androidfw/tests/Theme_test.cpp
index 55d53ed..2c39cee 100644
--- a/libs/androidfw/tests/Theme_test.cpp
+++ b/libs/androidfw/tests/Theme_test.cpp
@@ -21,12 +21,14 @@
 #include "TestHelpers.h"
 #include "androidfw/ResourceUtils.h"
 #include "data/lib_one/R.h"
+#include "data/lib_two/R.h"
 #include "data/libclient/R.h"
 #include "data/styles/R.h"
 #include "data/system/R.h"
 
 namespace app = com::android::app;
 namespace lib_one = com::android::lib_one;
+namespace lib_two = com::android::lib_two;
 namespace libclient = com::android::libclient;
 
 namespace android {
@@ -263,7 +265,7 @@
   ASSERT_TRUE(theme_two->ApplyStyle(app::R::style::StyleThree));
 
   // Copy the theme to theme_one.
-  ASSERT_TRUE(theme_one->SetTo(*theme_two));
+  theme_one->SetTo(*theme_two);
 
   // Clear theme_two to make sure we test that there WAS a copy.
   theme_two->Clear();
@@ -279,12 +281,14 @@
   EXPECT_EQ(static_cast<uint32_t>(ResTable_typeSpec::SPEC_PUBLIC), flags);
 }
 
-TEST_F(ThemeTest, OnlyCopySystemThemeWhenAssetManagersDiffer) {
+TEST_F(ThemeTest, OnlyCopySameAssetsThemeWhenAssetManagersDiffer) {
   AssetManager2 assetmanager_one;
-  assetmanager_one.SetApkAssets({system_assets_.get(), style_assets_.get()});
+  assetmanager_one.SetApkAssets({system_assets_.get(), lib_one_assets_.get(), style_assets_.get(),
+                                 libclient_assets_.get()});
 
   AssetManager2 assetmanager_two;
-  assetmanager_two.SetApkAssets({system_assets_.get(), style_assets_.get()});
+  assetmanager_two.SetApkAssets({system_assets_.get(), lib_two_assets_.get(), lib_one_assets_.get(),
+                                 style_assets_.get()});
 
   auto theme_one = assetmanager_one.NewTheme();
   ASSERT_TRUE(theme_one->ApplyStyle(app::R::style::StyleOne));
@@ -292,17 +296,34 @@
   auto theme_two = assetmanager_two.NewTheme();
   ASSERT_TRUE(theme_two->ApplyStyle(R::style::Theme_One));
   ASSERT_TRUE(theme_two->ApplyStyle(app::R::style::StyleTwo));
+  ASSERT_TRUE(theme_two->ApplyStyle(fix_package_id(lib_one::R::style::Theme, 0x03),
+                                    false /*force*/));
+  ASSERT_TRUE(theme_two->ApplyStyle(fix_package_id(lib_two::R::style::Theme, 0x02),
+                                    false /*force*/));
 
-  EXPECT_TRUE(theme_one->SetTo(*theme_two));
+  theme_one->SetTo(*theme_two);
 
   Res_value value;
   uint32_t flags;
 
-  // No app resources.
-  EXPECT_EQ(kInvalidCookie, theme_one->GetAttribute(app::R::attr::attr_one, &value, &flags));
+  // System resources (present in destination asset manager)
+  EXPECT_EQ(0, theme_one->GetAttribute(R::attr::foreground, &value, &flags));
 
-  // Only system.
-  EXPECT_NE(kInvalidCookie, theme_one->GetAttribute(R::attr::foreground, &value, &flags));
+  // The cookie of the style asset is 3 in the source and 2 in the destination.
+  // Check that the cookie has been rewritten to the destination values
+  EXPECT_EQ(2, theme_one->GetAttribute(app::R::attr::attr_one, &value, &flags));
+
+  // The cookie of the lib_one asset is 2 in the source and 1 in the destination.
+  // The package id of the lib_one package is 0x03 in the source and 0x02 in the destination
+  // Check that the cookie and packages have been rewritten to the destination values
+  EXPECT_EQ(1, theme_one->GetAttribute(fix_package_id(lib_one::R::attr::attr1, 0x02), &value,
+                                       &flags));
+  EXPECT_EQ(1, theme_one->GetAttribute(fix_package_id(lib_one::R::attr::attr2, 0x02), &value,
+                                       &flags));
+
+  // attr2 references an attribute in lib_one. Check that the resolution of the attribute value is
+  // correct after the value of attr2 had its package id rewritten to the destination package id
+  EXPECT_EQ(700, value.data);
 }
 
 }  // namespace android