[FIR] Add test imitating complex smart casts on descriptors

compiler/fir/resolve/testData/resolve/expresssions/genericDescriptor.kt

@@ -6,15 +6,21 @@ public interface Descriptor
 // FILE: ResolvedCall.java
 
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 public interface ResolvedCall<D extends Descriptor> {
     @NotNull
     D getResultingDescriptor();
+
+    @Nullable
+    D getCandidateDescriptor();
 }
 
 // FILE: test.kt
 
 val Descriptor.name = "123"
+fun Descriptor.correct(): Boolean = true
+fun Descriptor.foo() {}
 
 interface Call<D : Descriptor> {
     val resultingDescriptor: D
@@ -23,6 +29,10 @@ interface Call<D : Descriptor> {
 fun <D : Descriptor> test(call: Call<D>, resolvedCall: ResolvedCall<D>) {
     call.resultingDescriptor.name
     resolvedCall.resultingDescriptor.name
+
+    val resolvedDescriptor = resolvedCall.candidateDescriptor
+    if (resolvedDescriptor?.correct() != true) return
+    resolvedDescriptor.<!INAPPLICABLE_CANDIDATE!>foo<!>()
 }
 
 fun otherTest(call: Call<*>, resolvedCall: ResolvedCall<*>) {

compiler/fir/resolve/testData/resolve/expresssions/genericDescriptor.txt

@@ -1,6 +1,11 @@
 FILE: test.kt
     public final val R|Descriptor|.name: R|kotlin/String| = String(123)
         public get(): R|kotlin/String|
+    public final fun R|Descriptor|.correct(): R|kotlin/Boolean| {
+        ^correct Boolean(true)
+    }
+    public final fun R|Descriptor|.foo(): R|kotlin/Unit| {
+    }
     public abstract interface Call<D : R|Descriptor|> : R|kotlin/Any| {
         public abstract val resultingDescriptor: R|D|
             public get(): R|D|
@@ -9,6 +14,14 @@ FILE: test.kt
     public final fun <D : R|Descriptor|> test(call: R|Call<D>|, resolvedCall: R|ResolvedCall<D>|): R|kotlin/Unit| {
         R|<local>/call|.R|FakeOverride</Call.resultingDescriptor: R|D|>|.R|/name|
         R|<local>/resolvedCall|.R|/ResolvedCall.resultingDescriptor|.R|/name|
+        lval resolvedDescriptor: R|D?| = R|<local>/resolvedCall|.R|/ResolvedCall.candidateDescriptor|
+        when () {
+            !=(R|<local>/resolvedDescriptor|?.R|/correct|(), Boolean(true)) ->  {
+                ^test Unit
+            }
+        }
+
+        R|<local>/resolvedDescriptor|.<Inapplicable(WRONG_RECEIVER): [/foo]>#()
     }
     public final fun otherTest(call: R|Call<*>|, resolvedCall: R|ResolvedCall<*>|): R|kotlin/Unit| {
         R|<local>/call|.R|FakeOverride</Call.resultingDescriptor: R|Descriptor|>|.R|/name|