JS: support SAM conversion

The SAM adapter is generate on declaration site. This is different
from the JVM approach.

`external fun interface` is banned for now.

Reusing interface declaration for the adapter is a hack which
reduces code size and makes importing/exporting the adapter
effortless.

compiler/testData/codegen/box/funInterface/suspendFunInterfaceConversionCodegen.kt

@@ -1,11 +1,11 @@
 // !LANGUAGE: +NewInference +FunctionalInterfaceConversion +SamConversionPerArgument +SamConversionForKotlinFunctions
 // IGNORE_BACKEND_FIR: JVM_IR
-// IGNORE_BACKEND: JS, JS_IR
+// IGNORE_BACKEND: JS_IR
 // WITH_COROUTINES
 // WITH_RUNTIME
 
 import helpers.*
-import kotlin.coroutines.startCoroutine
+import kotlin.coroutines.*
 
 fun interface SuspendRunnable {
     suspend fun invoke()
@@ -17,11 +17,25 @@ fun run(r: SuspendRunnable) {
 
 var result = "initial"
 
+var resumingCallback: () -> Unit = {}
+
 suspend fun bar() {
+    // Generate proper state machine
+    suspendCoroutine<Unit> { cont ->
+        resumingCallback = {
+            cont.resume(Unit)
+        }
+    }
+
     result = "OK"
 }
 
 fun box(): String {
     run(::bar)
+
+    if (result != "initial") return "fail"
+
+    resumingCallback()
+
     return result
 }