Add missing dependency in layoutlib build file [DO NOT MERGE]

Add missing dependency on built_ext_data

Change-Id: I4e7cca7f6cbc7f5b7416ac9b85a9aec01e61ecd4
(cherry picked from commit 411b9691e3)

tools/layoutlib/Android.mk

@@ -53,6 +53,7 @@ include $(BUILD_SYSTEM)/base_rules.mk
 $(LOCAL_BUILT_MODULE): $(built_core_dep) \
                        $(built_framework_dep) \
                        $(built_ext_dep) \
+                       $(built_ext_data) \
                        $(built_layoutlib_create_jar)
 	$(hide) echo "host layoutlib_create: $@"
 	$(hide) mkdir -p $(dir $@)