Fix the path for findbugs.

Change-Id: I45485f1aeaf7fc3db2839f42829278d8c0ec97e3
diff --git a/core/java.mk b/core/java.mk
index 824ae6a..ac481ee 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -504,7 +504,7 @@
 $(findbugs_html) : $(findbugs_xml)
 	@mkdir -p $(dir $@)
 	@echo ConvertXmlToText: $@
-	$(hide) prebuilt/common/findbugs/bin/convertXmlToText -html:fancy.xsl $(PRIVATE_XML_FILE) \
+	$(hide) $(FINDBUGS_DIR)/convertXmlToText -html:fancy.xsl $(PRIVATE_XML_FILE) \
 	> $@
 
 $(LOCAL_MODULE)-findbugs : $(findbugs_html)