[FIR] Increase level of sequential when branches

Level of CFGNode is used to determine which call is a common one for
  creating node with union of arguments (to merge flow from multiple
  in-place lambdas). Before this change calls in different when branches
  may have same node level, which entail passing smartcasts from moddle of
  one branch to another

```
val x: Any = ...
when {
    ... -> run { x as String } // (1)
    ... -> {
        run {
            x.foo()
        } // (2)
        "hello"
    }
}
```

Call `(1)` was assumed as argument of call `(2)` which is incorrect

#KT-44814 Fixed

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/es6/semantics/IrJsCodegenBoxES6TestGenerated.java

@@ -25527,6 +25527,11 @@ public class IrJsCodegenBoxES6TestGenerated extends AbstractIrJsCodegenBoxES6Tes
             runTest("compiler/testData/codegen/box/smartCasts/kt44804.kt");
         }
 
+        @TestMetadata("kt44814.kt")
+        public void testKt44814() throws Exception {
+            runTest("compiler/testData/codegen/box/smartCasts/kt44814.kt");
+        }
+
         @TestMetadata("lambdaArgumentWithoutType.kt")
         public void testLambdaArgumentWithoutType() throws Exception {
             runTest("compiler/testData/codegen/box/smartCasts/lambdaArgumentWithoutType.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/semantics/IrJsCodegenBoxTestGenerated.java

@@ -25012,6 +25012,11 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/smartCasts/kt44804.kt");
         }
 
+        @TestMetadata("kt44814.kt")
+        public void testKt44814() throws Exception {
+            runTest("compiler/testData/codegen/box/smartCasts/kt44814.kt");
+        }
+
         @TestMetadata("lambdaArgumentWithoutType.kt")
         public void testLambdaArgumentWithoutType() throws Exception {
             runTest("compiler/testData/codegen/box/smartCasts/lambdaArgumentWithoutType.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -24972,6 +24972,11 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/smartCasts/kt44804.kt");
         }
 
+        @TestMetadata("kt44814.kt")
+        public void testKt44814() throws Exception {
+            runTest("compiler/testData/codegen/box/smartCasts/kt44814.kt");
+        }
+
         @TestMetadata("lambdaArgumentWithoutType.kt")
         public void testLambdaArgumentWithoutType() throws Exception {
             runTest("compiler/testData/codegen/box/smartCasts/lambdaArgumentWithoutType.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/wasm/semantics/IrCodegenBoxWasmTestGenerated.java

@@ -13589,6 +13589,11 @@ public class IrCodegenBoxWasmTestGenerated extends AbstractIrCodegenBoxWasmTest
             runTest("compiler/testData/codegen/box/smartCasts/kt44804.kt");
         }
 
+        @TestMetadata("kt44814.kt")
+        public void testKt44814() throws Exception {
+            runTest("compiler/testData/codegen/box/smartCasts/kt44814.kt");
+        }
+
         @TestMetadata("multipleSmartCast.kt")
         public void testMultipleSmartCast() throws Exception {
             runTest("compiler/testData/codegen/box/smartCasts/multipleSmartCast.kt");