Skip publishContentProviders() when we have zero.

If the list of providers for the application being bound is empty,
don't bother trying to register them.

Bug: 27510621
Change-Id: I921fb70a4c97433fa123fa88e170745ee013ee35

3 files changed, 14 insertions, 6 deletions

diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 14688c1bc1b9..a452d2047088 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -113,6 +113,7 @@ import com.android.internal.os.BinderInternal;
 import com.android.internal.os.RuntimeInit;
 import com.android.internal.os.SamplingProfilerIntegration;
 import com.android.internal.os.SomeArgs;
+import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.FastPrintWriter;
 import com.android.org.conscrypt.OpenSSLSocketImpl;
 import com.android.org.conscrypt.TrustedCertificateStore;
@@ -5264,9 +5265,8 @@ public final class ActivityThread {
             // don't bring up providers in restricted mode; they may depend on the
             // app's custom Application class
             if (!data.restrictedBackupMode) {
-                List<ProviderInfo> providers = data.providers;
-                if (providers != null) {
-                    installContentProviders(app, providers);
+                if (!ArrayUtils.isEmpty(data.providers)) {
+                    installContentProviders(app, data.providers);
                     // For process that contains content providers, we want to
                     // ensure that the JIT is enabled "at some point".
                     mH.sendEmptyMessageDelayed(H.ENABLE_JIT, 10*1000);
diff --git a/core/java/com/android/internal/util/ArrayUtils.java b/core/java/com/android/internal/util/ArrayUtils.java
index 80269493fa5e..a84a061077bf 100644
--- a/core/java/com/android/internal/util/ArrayUtils.java
+++ b/core/java/com/android/internal/util/ArrayUtils.java
@@ -27,6 +27,7 @@ import libcore.util.EmptyArray;
 import java.lang.reflect.Array;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 import java.util.Objects;
 
 /**
@@ -126,6 +127,13 @@ public class ArrayUtils {
     /**
      * Checks if given array is null or has zero elements.
      */
+    public static boolean isEmpty(@Nullable List<?> array) {
+        return array == null || array.isEmpty();
+    }
+
+    /**
+     * Checks if given array is null or has zero elements.
+     */
     public static <T> boolean isEmpty(@Nullable T[] array) {
         return array == null || array.length == 0;
     }
diff --git a/services/core/java/com/android/server/am/ActivityManagerService.java b/services/core/java/com/android/server/am/ActivityManagerService.java
index 8cea8ee06749..e22a0656f7c4 100644
--- a/services/core/java/com/android/server/am/ActivityManagerService.java
+++ b/services/core/java/com/android/server/am/ActivityManagerService.java
@@ -9902,11 +9902,11 @@ public final class ActivityManagerService extends ActivityManagerNative
     private final List<ProviderInfo> generateApplicationProvidersLocked(ProcessRecord app) {
         List<ProviderInfo> providers = null;
         try {
-            ParceledListSlice<ProviderInfo> slice = AppGlobals.getPackageManager()
+            providers = AppGlobals.getPackageManager()
                     .queryContentProviders(app.processName, app.uid,
                             STOCK_PM_FLAGS | PackageManager.GET_URI_PERMISSION_PATTERNS
-                                    | MATCH_DEBUG_TRIAGED_MISSING);
-            providers = slice != null ? slice.getList() : null;
+                                    | MATCH_DEBUG_TRIAGED_MISSING)
+                    .getList();
         } catch (RemoteException ex) {
         }
         if (DEBUG_MU) Slog.v(TAG_MU,