[stdlib] Use Kotlin/JVM implementation for regex split (#2100)

backend.native/tests/harmony_regex/MatchResultTest.kt

@@ -407,8 +407,9 @@ class MatchResultTest {
         val regex = Regex("")
         val s = regex.split("", 0)
 
-        assertEquals(1, s.size)
+        assertEquals(2, s.size)
         assertEquals("", s[0])
+        assertEquals("", s[1])
     }
 
     @Test fun testFindDollar() {

backend.native/tests/harmony_regex/PatternTest.kt

@@ -57,7 +57,7 @@ class PatternTest {
         assertEquals(s.size, 1)
         regex = Regex("")
         s = regex.split("", 0)
-        assertEquals(s.size, 1)
+        assertEquals(s.size, 2)
         s = regex.split("abccbadfe", 0)
         assertEquals(s.size, 11)
 
@@ -69,7 +69,7 @@ class PatternTest {
         assertEquals(s.size, 1)
         regex = Regex("")
         s = regex.split("", 11)
-        assertEquals(s.size, 1)
+        assertEquals(s.size, 2)
         s = regex.split("abccbadfe", 15)
         assertEquals(s.size, 11)
 

backend.native/tests/harmony_regex/SplitTest.kt

@@ -122,8 +122,9 @@ class SplitTest {
         assertEquals("", s[2])
 
         s = p.split("", 0)
-        assertEquals(1, s.size)
+        assertEquals(2, s.size)
         assertEquals("", s[0])
+        assertEquals("", s[1])
 
         s = p.split("abcd", 0)
         assertEquals(6, s.size)