fix bug in tree-diff.
fix bug in tree-diff.

hxddh/chromedeveditor,2947721120/chromedeveditor,hxddh/chromedeveditor,2947721120/choredev,b0dh1sattva/chromedeveditor,googlearchive/chromedeveditor,modulexcite/chromedeveditor,ussuri/chromedeveditor,valmzetvn/chromedeveditor,devoncarew/spark,yikaraman/chromedeveditor,devoncarew/spark,2947721120/chromedeveditor,modulexcite/chromedeveditor,2947721120/choredev,beaufortfrancois/chromedeveditor,googlearchive/chromedeveditor,b0dh1sattva/chromedeveditor,valmzetvn/chromedeveditor,2947721120/choredev,googlearchive/chromedeveditor,modulexcite/chromedeveditor,beaufortfrancois/chromedeveditor,googlearchive/chromedeveditor,devoncarew/spark,ussuri/chromedeveditor,vivalaralstin/chromedeveditor,hxddh/chromedeveditor,ussuri/chromedeveditor,vivalaralstin/chromedeveditor,googlearchive/chromedeveditor,2947721120/choredev,devoncarew/spark,vivalaralstin/chromedeveditor,modulexcite/chromedeveditor,modulexcite/chromedeveditor,hxddh/chromedeveditor,yikaraman/chromedeveditor,yikaraman/chromedeveditor,valmzetvn/chromedeveditor,b0dh1sattva/chromedeveditor,valmzetvn/chromedeveditor,2947721120/choredev,2947721120/chromedeveditor,yikaraman/chromedeveditor,2947721120/choredev,ussuri/chromedeveditor,devoncarew/spark,2947721120/choredev,beaufortfrancois/chromedeveditor,googlearchive/chromedeveditor,b0dh1sattva/chromedeveditor,ussuri/chromedeveditor,valmzetvn/chromedeveditor,beaufortfrancois/chromedeveditor,b0dh1sattva/chromedeveditor,yikaraman/chromedeveditor,beaufortfrancois/chromedeveditor,modulexcite/chromedeveditor,devoncarew/spark,vivalaralstin/chromedeveditor,googlearchive/chromedeveditor,beaufortfrancois/chromedeveditor,ussuri/chromedeveditor,2947721120/chromedeveditor,modulexcite/chromedeveditor,yikaraman/chromedeveditor,hxddh/chromedeveditor,vivalaralstin/chromedeveditor,b0dh1sattva/chromedeveditor,2947721120/chromedeveditor,b0dh1sattva/chromedeveditor,2947721120/chromedeveditor,hxddh/chromedeveditor,ussuri/chromedeveditor,2947721120/chromedeveditor,hxddh/chromedeveditor,vivalaralstin/chromedeveditor,yikaraman/chromedeveditor,valmzetvn/chromedeveditor,valmzetvn/chromedeveditor,beaufortfrancois/chromedeveditor,vivalaralstin/chromedeveditor