Merge fix for #1957 to mainline and #1884. Fixes #1957. [t:1884] close[t:1957]

git-svn-id: file:///svn/toku/tokudb@14113 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/brt-serialize.c

@@ -557,6 +557,7 @@ int toku_serialize_brtnode_to (int fd, BLOCKNUM blocknum, BRTNODE node, struct b
     assert(w.ndone==calculated_size);
     toku_free(buf);
     toku_free(compressed_buf);
+    node->dirty = 0;  // See #1957.   Must set the node to be clean after serializing it so that it doesn't get written again on the next checkpoint or eviction.
     return r;
 }