More precise diagnostics is added for smart cast impossible #KT-8810 Fixed

compiler/testData/diagnostics/tests/smartCasts/fieldInGetter.kt

@@ -0,0 +1,5 @@
+val x: Int? = 0
+    get() {
+        if (field != null) return <!DEBUG_INFO_SMARTCAST!>field<!>.hashCode()
+        return null
+    }

compiler/testData/diagnostics/tests/smartCasts/fieldInGetter.txt

@@ -0,0 +1,3 @@
+package
+
+public val x: kotlin.Int? = 0