Java: Add up/downgrade scripts

java/downgrades/876cabc76c5c83912271db331481f8cba2749643/fields.ql

@@ -0,0 +1,15 @@
+class Field extends @field {
+  string toString() { none() }
+}
+
+class Type extends @type {
+  string toString() { none() }
+}
+
+class RefType extends @reftype {
+  string toString() { none() }
+}
+
+from Field f, string name, Type t, RefType parent
+where fields(f, name, t, parent)
+select f, name, t, parent, f

java/downgrades/876cabc76c5c83912271db331481f8cba2749643/upgrade.properties

@@ -0,0 +1,3 @@
+description: Remove fields.sourceid
+compatibility: full
+fields.rel: run fields.qlo

java/ql/lib/upgrades/376ce7dad79375c0772b8edb938da82ca5271ba1/fields.ql

@@ -0,0 +1,15 @@
+class Field extends @field {
+  string toString() { none() }
+}
+
+class Type extends @type {
+  string toString() { none() }
+}
+
+class RefType extends @reftype {
+  string toString() { none() }
+}
+
+from Field f, string name, Type t, RefType parent
+where fields(f, name, t, parent, _)
+select f, name, t, parent

java/ql/lib/upgrades/376ce7dad79375c0772b8edb938da82ca5271ba1/upgrade.properties

@@ -0,0 +1,3 @@
+description: Remove fields.sourceid
+compatibility: full
+fields.rel: run fields.qlo