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

2 files changed, 14 insertions, 2 deletions

diff --git a/core/java/android/content/res/AssetManager.java b/core/java/android/content/res/AssetManager.java
index 0350effd84b8..5f2374995775 100644
--- a/core/java/android/content/res/AssetManager.java
+++ b/core/java/android/content/res/AssetManager.java
@@ -1064,6 +1064,17 @@ public final class AssetManager implements AutoCloseable {
         }
     }
 
+    @UnsupportedAppUsage
+    void setThemeTo(long dstThemePtr, @NonNull AssetManager srcAssetManager, long srcThemePtr) {
+        synchronized (this) {
+            ensureValidLocked();
+            synchronized (srcAssetManager) {
+                srcAssetManager.ensureValidLocked();
+                nativeThemeCopy(mObject, dstThemePtr, srcAssetManager.mObject, srcThemePtr);
+            }
+        }
+    }
+
     @Override
     protected void finalize() throws Throwable {
         if (DEBUG_REFS && mNumRefs != 0) {
@@ -1375,7 +1386,8 @@ public final class AssetManager implements AutoCloseable {
     private static native void nativeThemeDestroy(long themePtr);
     private static native void nativeThemeApplyStyle(long ptr, long themePtr, @StyleRes int resId,
             boolean force);
-    static native void nativeThemeCopy(long destThemePtr, long sourceThemePtr);
+    private static native void nativeThemeCopy(long dstAssetManagerPtr, long dstThemePtr,
+            long srcAssetManagerPtr, long srcThemePtr);
     static native void nativeThemeClear(long themePtr);
     private static native int nativeThemeGetAttributeValue(long ptr, long themePtr,
             @AttrRes int resId, @NonNull TypedValue outValue, boolean resolve);
diff --git a/core/java/android/content/res/ResourcesImpl.java b/core/java/android/content/res/ResourcesImpl.java
index dfa30a22597e..0f5546b79fef 100644
--- a/core/java/android/content/res/ResourcesImpl.java
+++ b/core/java/android/content/res/ResourcesImpl.java
@@ -1335,7 +1335,7 @@ public class ResourcesImpl {
         void setTo(ThemeImpl other) {
             synchronized (mKey) {
                 synchronized (other.mKey) {
-                    AssetManager.nativeThemeCopy(mTheme, other.mTheme);
+                    mAssets.setThemeTo(mTheme, other.mAssets, other.mTheme);
 
                     mThemeResId = other.mThemeResId;
                     mKey.setTo(other.getKey());