make JSRuntime.importValue consistent with ImportValueNode

Author: wirthi

graal-js/src/com.oracle.truffle.js.test/src/com/oracle/truffle/js/test/runtime/JSRuntimeTest.java

@@ -165,7 +165,7 @@ public void testImportValue() {
         assertSame(42, JSRuntime.importValue((short) 42));
 
         assertSame(42, JSRuntime.importValue(42L));
-        assertEquals(BigInt.valueOf(Long.MAX_VALUE), JSRuntime.importValue(Long.MAX_VALUE));
+        assertEquals(Long.MAX_VALUE, JSRuntime.importValue(Long.MAX_VALUE));
         assertEquals(42.0, (double) JSRuntime.importValue((float) 42), BIGDELTA);
 
         try {

graal-js/src/com.oracle.truffle.js/src/com/oracle/truffle/js/runtime/JSRuntime.java

@@ -2816,7 +2816,7 @@ public static Object[] exportValueArray(Object[] arr) {
 
     /**
      * Convert the value to a type valid in Graal.js, from something received via TruffleInterop.
-     * Use JSForeignToJSTypeNode where possible.
+     * Use ImportValueNode where possible.
      */
     @TruffleBoundary
     public static Object importValue(Object value) {
@@ -2831,7 +2831,7 @@ public static Object importValue(Object value) {
             if (longIsRepresentableAsInt(longValue)) {
                 return (int) longValue;
             } else {
-                return BigInt.valueOf(longValue);
+                return longValue;
             }
         } else if (value instanceof Byte || value instanceof Short) {
             return ((Number) value).intValue();