Add missing sum() on Streams.

libraries/stdlib/src/generated/_Numeric.kt

@@ -19,6 +19,18 @@ public fun Iterable<Int>.sum(): Int {
     return sum
 }
 
+/**
+ * Returns the sum of all elements in the collection
+ */
+public fun Stream<Int>.sum(): Int {
+    val iterator = iterator()
+    var sum: Int = 0
+    while (iterator.hasNext()) {
+        sum += iterator.next()
+    }
+    return sum
+}
+
 /**
  * Returns the sum of all elements in the collection
  */
@@ -31,6 +43,18 @@ public fun Iterable<Long>.sum(): Long {
     return sum
 }
 
+/**
+ * Returns the sum of all elements in the collection
+ */
+public fun Stream<Long>.sum(): Long {
+    val iterator = iterator()
+    var sum: Long = 0
+    while (iterator.hasNext()) {
+        sum += iterator.next()
+    }
+    return sum
+}
+
 /**
  * Returns the sum of all elements in the collection
  */
@@ -43,6 +67,18 @@ public fun Iterable<Double>.sum(): Double {
     return sum
 }
 
+/**
+ * Returns the sum of all elements in the collection
+ */
+public fun Stream<Double>.sum(): Double {
+    val iterator = iterator()
+    var sum: Double = 0.0
+    while (iterator.hasNext()) {
+        sum += iterator.next()
+    }
+    return sum
+}
+
 /**
  * Returns the sum of all elements in the collection
  */
@@ -55,6 +91,18 @@ public fun Iterable<Float>.sum(): Float {
     return sum
 }
 
+/**
+ * Returns the sum of all elements in the collection
+ */
+public fun Stream<Float>.sum(): Float {
+    val iterator = iterator()
+    var sum: Float = 0.0f
+    while (iterator.hasNext()) {
+        sum += iterator.next()
+    }
+    return sum
+}
+
 /**
  * Returns the sum of all elements in the collection
  */