btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root

Now that we have a dummy fs_info associated with each test that
uses a root, we don't need the DUMMY_ROOT bit anymore.  This lets
us make choices without needing an actual root like in e.g.
btrfs_find_create_tree_block.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index b166ee0..3f0311b 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1744,7 +1744,7 @@
 		}
 
 		/* For sanity tests */
-		if (btrfs_test_is_dummy_root(root))
+		if (btrfs_is_testing(root->fs_info))
 			return;
 
 		__percpu_counter_add(&root->fs_info->delalloc_bytes, len,
@@ -1803,7 +1803,7 @@
 			btrfs_delalloc_release_metadata(inode, len);
 
 		/* For sanity tests. */
-		if (btrfs_test_is_dummy_root(root))
+		if (btrfs_is_testing(root->fs_info))
 			return;
 
 		if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID