Avoid hitting max argument limit in String(chars)

Rewrite CharArray to String conversions to appending chars one by one.

Refine parameter checking in String(chars, offset, length) to adhere to
the common exception contract and document it.

#KT-29003

libraries/stdlib/js/src/kotlin/string.kt

@@ -11,17 +11,29 @@ import kotlin.js.RegExp
  * Converts the characters in the specified array to a string.
  */
 @SinceKotlin("1.2")
-@kotlin.internal.InlineOnly
-public actual inline fun String(chars: CharArray): String {
-    return js("String.fromCharCode").apply(null, chars)
+public actual fun String(chars: CharArray): String {
+    var result = ""
+    for (char in chars) {
+        result += char
+    }
+    return result
 }
 
 /**
  * Converts the characters from a portion of the specified array to a string.
+ *
+ * @throws IndexOutOfBoundsException if either [offset] or [length] are less than zero
+ * or `offset + length` is out of [chars] array bounds.
  */
 @SinceKotlin("1.2")
 public actual fun String(chars: CharArray, offset: Int, length: Int): String {
-    return String(chars.copyOfRange(offset, offset + length))
+    if (offset < 0 || length < 0 || chars.size - offset < length)
+        throw IndexOutOfBoundsException("size: ${chars.size}; offset: $offset; length: $length")
+    var result = ""
+    for (index in offset until offset + length) {
+        result += chars[index]
+    }
+    return result
 }
 
 /**