Autocasts for 'this' and stable qualified expressions

idea/testData/checker/infos/Autocasts.jet

@@ -189,11 +189,11 @@ fun tuples(a: Any?) {
         val s: (Any, String) = (<info descr="Automatically cast to Any">a</info>, <error descr="[TYPE_MISMATCH] Type mismatch: inferred type is Any? but String was expected">a</error>)
     }
     if (a is String) {
-        val s: (Any, String) = (<info descr="Automatically cast to String">a</info>, <info descr="Automatically cast to String">a</info>)
+        val s: (Any, String) = (<info descr="Automatically cast to Any">a</info>, <info descr="Automatically cast to String">a</info>)
     }
     fun illegalTupleReturnType(): (Any, String) = (<error descr="[TYPE_MISMATCH] Type mismatch: inferred type is Any? but Any was expected">a</error>, <error descr="[TYPE_MISMATCH] Type mismatch: inferred type is Any? but String was expected">a</error>)
     if (a is String) {
-        fun legalTupleReturnType(): (Any, String) = (<info descr="Automatically cast to String">a</info>, <info descr="Automatically cast to String">a</info>)
+        fun legalTupleReturnType(): (Any, String) = (<info descr="Automatically cast to Any">a</info>, <info descr="Automatically cast to String">a</info>)
     }
     val illegalFunctionLiteral: Function0<Int> = <error descr="[TYPE_MISMATCH] Type mismatch: inferred type is Function0<Any?> but Function0<Int> was expected">{ <error descr="[TYPE_MISMATCH] Type mismatch: inferred type is Any? but Int was expected">a</error> }</error>
     val illegalReturnValueInFunctionLiteral: Function0<Int> = { (): Int => <error descr="[TYPE_MISMATCH] Type mismatch: inferred type is Any? but Int was expected">a</error> }

idea/testData/checkerWithErrorTypes/quick/AutocastsForStableIdentifiers.jet

@@ -0,0 +1,91 @@
+namespace example;
+
+namespace ns {
+    val y : Any? = 2
+}
+
+object Obj {
+    val y : Any? = 2
+}
+
+class AClass() {
+    class object {
+        val y : Any? = 2
+    }
+}
+
+val x : Any? = 1
+
+fun Any?.vars(a: Any?) : Int {
+    var b: Int = 0
+    if (ns.y is Int) {
+        b = ns.y
+    }
+    if (ns.y is Int) {
+        b = example.ns.y
+    }
+    if (example.ns.y is Int) {
+        b = ns.y
+    }
+    if (example.ns.y is Int) {
+        b = example.ns.y
+    }
+//    if (namespace.bottles.ns.y is Int) {
+//        b = ns.y
+//    }
+    if (Obj.y is Int) {
+        b = Obj.y
+    }
+    if (example.Obj.y is Int) {
+        b = Obj.y
+    }
+    if (AClass.y is Int) {
+        b = AClass.y
+    }
+    if (example.AClass.y is Int) {
+        b = AClass.y
+    }
+    if (x is Int) {
+        b = x
+    }
+    if (example.x is Int) {
+        b = x
+    }
+    if (example.x is Int) {
+        b = example.x
+    }
+    return 1
+}
+
+fun Any?.foo() : Int {
+    if (this is Int)
+      return this
+    if (this@foo is Int)
+      return this
+    if (this@foo is Int)
+      return this@foo
+    if (this is Int)
+      return this@foo
+    return 1
+}
+
+
+trait T {}
+
+open class C {
+    fun foo() {
+       var t : T? = null
+       if (this is T) {
+          t = this
+       }
+       if (this is T) {
+          t = this@C
+       }
+       if (this@C is T) {
+          t = this
+       }
+       if (this@C is T) {
+          t = this@C
+       }
+    }
+}