Fix NPE when we can't find the volume for a file.

If for some reason we can't get a volume associated with a file, don't
NPE, and just open through MP.

Bug: 146820192
Test: builds
Change-Id: I362c9222428758cbe97b638622b09d0e40fc27e7
diff --git a/src/com/android/providers/media/MediaProvider.java b/src/com/android/providers/media/MediaProvider.java
index 0dc41fb..c64c4ff 100644
--- a/src/com/android/providers/media/MediaProvider.java
+++ b/src/com/android/providers/media/MediaProvider.java
@@ -4398,8 +4398,12 @@
                             redactionInfo.freeOffsets);
                 }
             } else {
+                FuseDaemon daemon = null;
+
                 StorageVolume volume = mStorageManager.getStorageVolume(file);
-                FuseDaemon daemon = ExternalStorageServiceImpl.getFuseDaemon(volume.getId());
+                if (volume != null) {
+                    daemon = ExternalStorageServiceImpl.getFuseDaemon(volume.getId());
+                }
                 ParcelFileDescriptor lowerFsFd = ParcelFileDescriptor.open(file, modeBits);
                 boolean forRead = (modeBits & ParcelFileDescriptor.MODE_READ_ONLY) != 0;
                 boolean shouldOpenWithFuse = daemon != null