JS: Provide MIN_VALUE and MAX_VALUE member constants for Int, Long, Short and Byte companion objects.

JVM: Make MIN_VALUE and MAX_VALUE not an extension but member constant properties of Int, Long, Short and Byte companion objects.

libraries/stdlib/test/numbers/NumbersTest.kt

@@ -5,6 +5,40 @@ import kotlin.test.*
 
 class NumbersTest {
 
+
+    test fun intMinMaxValues() {
+        assertTrue(Int.MIN_VALUE < 0)
+        assertTrue(Int.MAX_VALUE > 0)
+
+        // overflow behavior
+        // doesn't hold for JS Number
+        // assertEquals(Int.MIN_VALUE, Int.MAX_VALUE + 1)
+    }
+
+    test fun longMinMaxValues() {
+        assertTrue(Long.MIN_VALUE < 0)
+        assertTrue(Long.MAX_VALUE > 0)
+        // overflow behavior
+        assertEquals(Long.MIN_VALUE, Long.MAX_VALUE + 1)
+        assertEquals(Long.MAX_VALUE, Long.MIN_VALUE - 1)
+    }
+
+    test fun shortMinMaxValues() {
+        assertTrue(Short.MIN_VALUE < 0)
+        assertTrue(Short.MAX_VALUE > 0)
+        // overflow behavior
+        assertEquals(Short.MIN_VALUE, (Short.MAX_VALUE + 1).toShort())
+        assertEquals(Short.MAX_VALUE, (Short.MIN_VALUE - 1).toShort())
+    }
+
+    test fun byteMinMaxValues() {
+        assertTrue(Byte.MIN_VALUE < 0)
+        assertTrue(Byte.MAX_VALUE > 0)
+        // overflow behavior
+        assertEquals(Byte.MIN_VALUE, (Byte.MAX_VALUE + 1).toByte())
+        assertEquals(Byte.MAX_VALUE, (Byte.MIN_VALUE - 1).toByte())
+    }
+
     test fun doubleProperties() {
         for (value in listOf(1.0, 0.0))
             doTestNumber(value)