Fix NPE in deleteDatabase().

If the directory containing the database does not exist then
listFiles() will return null.  Tolerate this situation instead
of crashing.

Bug: 12600784
Change-Id: I5d83a867a5e8478f50887e5798b42c5f6859b77c

1 files changed, 6 insertions, 4 deletions

diff --git a/core/java/android/database/sqlite/SQLiteDatabase.java b/core/java/android/database/sqlite/SQLiteDatabase.java
index 60ccc61..433d5d1 100644
--- a/core/java/android/database/sqlite/SQLiteDatabase.java
+++ b/core/java/android/database/sqlite/SQLiteDatabase.java
@@ -738,14 +738,16 @@ public final class SQLiteDatabase extends SQLiteClosable {
         File dir = file.getParentFile();
         if (dir != null) {
             final String prefix = file.getName() + "-mj";
-            final FileFilter filter = new FileFilter() {
+            File[] files = dir.listFiles(new FileFilter() {
                 @Override
                 public boolean accept(File candidate) {
                     return candidate.getName().startsWith(prefix);
                 }
-            };
-            for (File masterJournal : dir.listFiles(filter)) {
-                deleted |= masterJournal.delete();
+            });
+            if (files != null) {
+                for (File masterJournal : files) {
+                    deleted |= masterJournal.delete();
+                }
             }
         }
         return deleted;