Add jdiff support for Soong

Test: api-stubs-docs-diff
Bug: b/78245848
Change-Id: I069f6f8b1f9aa74ae1425cd5b792643d05b26820
diff --git a/java/androidmk.go b/java/androidmk.go
index 509ad94..57f57cc 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -397,6 +397,9 @@
 				if dstubs.annotationsZip != nil {
 					fmt.Fprintln(w, "LOCAL_DROIDDOC_ANNOTATIONS_ZIP := ", dstubs.annotationsZip.String())
 				}
+				if dstubs.jdiffDocZip != nil {
+					fmt.Fprintln(w, "LOCAL_DROIDDOC_JDIFF_DOC_ZIP := ", dstubs.jdiffDocZip.String())
+				}
 				if dstubs.checkCurrentApiTimestamp != nil {
 					fmt.Fprintln(w, ".PHONY:", dstubs.Name()+"-check-current-api")
 					fmt.Fprintln(w, dstubs.Name()+"-check-current-api:",