[Wasm] Pass js stack value directly when replacing a wasm exception with JS one

In this case, we don't need to convert a value to and from wasm String.

libraries/stdlib/wasm/builtins/kotlin/Throwable.kt

@@ -22,7 +22,7 @@ public open class Throwable(open val message: String?, open val cause: kotlin.Th
 
     constructor() : this(null, null)
 
-    private val jsStack: ExternalInterfaceType = captureStackTrace()
+    internal val jsStack: ExternalInterfaceType = captureStackTrace()
 
     private var _stack: String? = null
     internal val stack: String

libraries/stdlib/wasm/internal/kotlin/wasm/internal/ExceptionHelpers.kt

@@ -6,7 +6,7 @@
 package kotlin.wasm.internal
 
 @Suppress("UNUSED_PARAMETER") // TODO: Remove after bootstrap update
-private fun throwJsError(message: String?, wasmTypeName: String?, stack: String): Nothing {
+private fun throwJsError(message: String?, wasmTypeName: String?, stack: ExternalInterfaceType): Nothing {
     js("""
     const error = new Error();
     error.message = message;
@@ -17,7 +17,7 @@ private fun throwJsError(message: String?, wasmTypeName: String?, stack: String)
 }
 
 internal fun throwAsJsException(t: Throwable): Nothing {
-    throwJsError(t.message, getSimpleName(t.typeInfo), t.stack)
+    throwJsError(t.message, getSimpleName(t.typeInfo), t.jsStack)
 }
 
 internal var isNotFirstWasmExportCall: Boolean = false