Preliminary declaration visitor for estimating local variable's predictability for smart casts

Predictability estimation algorithm is completely new, but backward compatibility should present.
A large set of tests. Some updated tests.
Smart casts allowed for captured variables if they are not modified in closure #KT-9051 Fixed
Also #KT-8643 Fixed
Also #KT-7976 Fixed
Correct handling of lambda arguments in functions #KT-9143 Fixed

compiler/testData/diagnostics/testsWithStdLib/smartcasts/forEachSafe.kt

@@ -0,0 +1,11 @@
+// KT-7186: False "Type mismatch" error
+
+fun indexOfMax(a: IntArray): Int? {
+    var maxI: Int? = null
+    a.forEachIndexed { i, value ->
+        if (maxI == null || value >= a[<!TYPE_MISMATCH!>maxI<!>]) {
+            maxI = i
+        }
+    }
+    return maxI
+}