Add null check to SQLiteConnectionPool.dump()

This change adds a null check before adding the current connection
pool path's parent to the list of directories, since the parent might be
null. This avoids an NPE in SQLiteDatabase.dumpAll().

Test: run dumpsys dbinfo, verify that it no longer times out
Bug: 281043011
Change-Id: Iec7fa9d0941d79dfa034f117c35c30797c7d3113

core/java/android/database/sqlite/SQLiteConnectionPool.java

@@ -1136,7 +1136,10 @@ public final class SQLiteConnectionPool implements Closeable {
         Printer indentedPrinter = PrefixPrinter.create(printer, "    ");
         synchronized (mLock) {
             if (directories != null) {
-                directories.add(new File(mConfiguration.path).getParent());
+                String parent = new File(mConfiguration.path).getParent();
+                if (parent != null) {
+                    directories.add(parent);
+                }
             }
             boolean isCompatibilityWalEnabled = mConfiguration.isLegacyCompatibilityWalEnabled();
             printer.println("Connection pool for " + mConfiguration.path + ":");