Support for checking loaded descriptors agains an expected txt file

compiler/testData/lazyResolve/diagnostics/backingField/ReadInFunction.txt

@@ -0,0 +1,7 @@
+namespace <root>
+
+internal final class ReadByAnotherPropertyInitializer : jet.Any {
+    public final /*constructor*/ fun <init>(): ReadByAnotherPropertyInitializer
+    internal final val a: jet.Int
+    internal final fun ff(): jet.Int
+}