[FIR] Introduce new algorithm for building CFG for declarations

compiler/fir/analysis-tests/testData/resolve/cfg/defaultArguments.kt

@@ -0,0 +1,7 @@
+// !DUMP_CFG
+
+fun foo(): Int = 1
+
+fun test(x: Any, y: String = x as String, z: Int = run { foo() }) {
+    foo()
+}