Deprecate parseInt and parseFloat. Replace deprecated usages in tests.

#KT-4497

js/js.translator/testData/webDemoExamples1/cases/ifAsExpression.kt

@@ -1,5 +1,3 @@
 fun main(args: Array<String>) {
-    println(max(parseInt(args[0]), parseInt(args[1])))
+    println(maxOf(args[0].toInt(), args[1].toInt()))
 }
-
-fun max(a: Int, b: Int) = if (a > b) a else b

js/js.translator/testData/webDemoExamples1/cases/nullChecks.kt

@@ -1,12 +1,6 @@
 // Return null if str does not hold a number
-fun myParseInt(str: String): Int? {
-    try {
-        return parseInt(str)
-    }
-    catch (e: NumberFormatException) {
-        println("One of argument isn't Int")
-    }
-    return null
+fun myParseInt(str: String): Int? = str.toIntOrNull().also {
+    if (it == null) println("One of arguments isn't Int")
 }
 
 fun main(args: Array<String>) {

js/js.translator/testData/webDemoExamples1/cases/ranges.kt

@@ -1,6 +1,6 @@
 
 fun main(args: Array<String>) {
-    val x = parseInt(args[0])
+    val x = args[0].toInt()
     //Check if a number lies within a range:
     val y = 10
     if (x in 1..y - 1)