Don't insert entries with trailing slash

Directories should be be inserted without trailing slash.
MTP could insert a duplicate with a trailing slash, as a child of the
original, resulting in a bogus directory entry.

Bug: 31526567
Change-Id: Ia699a2390f93b98eeb087e37349f5fe28cf88ec7
diff --git a/src/com/android/providers/media/MediaProvider.java b/src/com/android/providers/media/MediaProvider.java
index d5b36da..a8048f4 100644
--- a/src/com/android/providers/media/MediaProvider.java
+++ b/src/com/android/providers/media/MediaProvider.java
@@ -3214,6 +3214,10 @@
                 format = MediaFile.getFormatCode(path, mimeType);
             }
         }
+        if (path.endsWith("/")) {
+            Log.e(TAG, "directory has trailing slash: " + path);
+            return 0;
+        }
         if (format != 0) {
             values.put(FileColumns.FORMAT, format);
             if (mimeType == null) {