Fix tests after introducing exlcusions to default imports of kotlin.js package.

idea/testData/editor/optimizeImports/js/DefaultJsImports.kt

@@ -1,7 +1,12 @@
+import kotlin.js.json
 import kotlin.js.Json
+import kotlin.js.JSON
+import kotlin.js.undefined
 
 fun main(args: Array<String>) {
-    val a: Json? = null
+    val a: dynamic = undefined
+    val b = JSON.stringify(a)
+    val j: Json = json("a" to 1)
 }
 
 // For KT-3620 Don't auto-import kotlin.js.* and remove in `optimize imports`

idea/testData/editor/optimizeImports/js/DefaultJsImports.kt.after

@@ -1,5 +1,10 @@
+import kotlin.js.Json
+import kotlin.js.json
+
 fun main(args: Array<String>) {
-    val a: Json? = null
+    val a: dynamic = undefined
+    val b = JSON.stringify(a)
+    val j: Json = json("a" to 1)
 }
 
 // For KT-3620 Don't auto-import kotlin.js.* and remove in `optimize imports`

idea/testData/editor/optimizeImports/js/DefaultJsImports.kt.log

@@ -0,0 +1,4 @@
+Additional checking of reference Getter: JSON
+Additional checking of reference KtSimpleNameReference: JSON
+Additional checking of reference Getter: undefined
+Additional checking of reference KtSimpleNameReference: undefined