Java: merge the @class and @interface database types and tables

This will allow the extractor to emit class(id, ...) when all it knows about a class is its name, due to not having it available on the classpath. Previously it would have had to guess whether it belonged to @class or @interface, possibly introducing an inconsistency.

java/downgrades/934bf10b4bd34cf648893efcd1d0d7be9471d39f/classes.ql

@@ -0,0 +1,11 @@
+class ClassOrInterface extends @classorinterface {
+  string toString() { result = "class-or-interface" }
+}
+
+class Package extends @package {
+  string toString() { result = "package" }
+}
+
+from ClassOrInterface id, string nodeName, Package parentId, ClassOrInterface sourceId
+where classes_or_interfaces(id, nodeName, parentId, sourceId) and not isInterface(id)
+select id, nodeName, parentId, sourceId

java/downgrades/934bf10b4bd34cf648893efcd1d0d7be9471d39f/interfaces.ql

@@ -0,0 +1,11 @@
+class ClassOrInterface extends @classorinterface {
+  string toString() { result = "class-or-interface" }
+}
+
+class Package extends @package {
+  string toString() { result = "package" }
+}
+
+from ClassOrInterface id, string nodeName, Package parentId, ClassOrInterface sourceId
+where classes_or_interfaces(id, nodeName, parentId, sourceId) and isInterface(id)
+select id, nodeName, parentId, sourceId

java/downgrades/934bf10b4bd34cf648893efcd1d0d7be9471d39f/upgrade.properties

@@ -0,0 +1,5 @@
+description: Seperate class and interface tables
+compatibility: full
+classes.rel: run classes.qlo
+interfaces.rel: run interfaces.qlo
+isInterface.rel: delete