UNNECESSARY_LATEINIT: do not report if property is not initialized at use-site #KT-13806 Fixed

(cherry picked from commit 09c0865)

compiler/testData/diagnostics/tests/controlFlowAnalysis/unnecessaryLateinit/lateinitRecursiveInLambda.kt

@@ -0,0 +1,6 @@
+class Test {
+    lateinit var someRunnable: Runnable
+    init {
+        someRunnable = Runnable { someRunnable.run() }
+    }
+}

compiler/testData/diagnostics/tests/controlFlowAnalysis/unnecessaryLateinit/lateinitRecursiveInLambda.txt

@@ -0,0 +1,9 @@
+package
+
+public final class Test {
+    public constructor Test()
+    public final lateinit var someRunnable: java.lang.Runnable
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/controlFlowAnalysis/unnecessaryLateinit/lateinitWithPlusAssign.kt

@@ -1,10 +1,8 @@
 class Foo {
-    // Erroneous case: after lateinit removal, we'll have error at 'bar += baz', not here
-    // However, looks like we must have error at 'bar += baz' even with lateinit
-    // because nobody can initialize this 'bar' before constructor is called
-    <!UNNECESSARY_LATEINIT!>lateinit<!> var bar: String
+    lateinit var bar: String
 
     constructor(baz: Int) {
+        // At best, we should have error here despite of lateinit
         bar += baz
     }
 }