Add Iterable.fold (and Stream.fold) which replace `reduce`.

sdk/lib/svg/dartium/svg_dartium.dart

Index: sdk/lib/svg/dartium/svg_dartium.dart
diff --git a/sdk/lib/svg/dartium/svg_dartium.dart b/sdk/lib/svg/dartium/svg_dartium.dart
index a837e5bdb50112906f5deb2fc1bbe61bd8de3d10..a665e68dc8f78cb6ece33f6dd0ed94dee4d16655 100644
--- a/sdk/lib/svg/dartium/svg_dartium.dart
+++ b/sdk/lib/svg/dartium/svg_dartium.dart
@@ -3336,6 +3336,10 @@ class LengthList extends NativeFieldWrapperClass1 implements List<Length> {
     return IterableMixinWorkaround.reduce(this, initialValue, combine);
   }
 
+  dynamic fold(dynamic initialValue, dynamic combine(dynamic, Length)) {
+    return IterableMixinWorkaround.fold(this, initialValue, combine);
+  }
+
   bool contains(Length element) => IterableMixinWorkaround.contains(this, element);
 
   void forEach(void f(Length element)) => IterableMixinWorkaround.forEach(this, f);
@@ -4047,6 +4051,10 @@ class NumberList extends NativeFieldWrapperClass1 implements List<Number> {
     return IterableMixinWorkaround.reduce(this, initialValue, combine);
   }
 
+  dynamic fold(dynamic initialValue, dynamic combine(dynamic, Number)) {
+    return IterableMixinWorkaround.fold(this, initialValue, combine);
+  }
+
   bool contains(Number element) => IterableMixinWorkaround.contains(this, element);
 
   void forEach(void f(Number element)) => IterableMixinWorkaround.forEach(this, f);
@@ -5234,6 +5242,10 @@ class PathSegList extends NativeFieldWrapperClass1 implements List<PathSeg> {
     return IterableMixinWorkaround.reduce(this, initialValue, combine);
   }
 
+  dynamic fold(dynamic initialValue, dynamic combine(dynamic, PathSeg)) {
+    return IterableMixinWorkaround.fold(this, initialValue, combine);
+  }
+
   bool contains(PathSeg element) => IterableMixinWorkaround.contains(this, element);
 
   void forEach(void f(PathSeg element)) => IterableMixinWorkaround.forEach(this, f);
@@ -6226,6 +6238,10 @@ class StringList extends NativeFieldWrapperClass1 implements List<String> {
     return IterableMixinWorkaround.reduce(this, initialValue, combine);
   }
 
+  dynamic fold(dynamic initialValue, dynamic combine(dynamic, String)) {
+    return IterableMixinWorkaround.fold(this, initialValue, combine);
+  }
+
   bool contains(String element) => IterableMixinWorkaround.contains(this, element);
 
   void forEach(void f(String element)) => IterableMixinWorkaround.forEach(this, f);
@@ -7487,6 +7503,10 @@ class TransformList extends NativeFieldWrapperClass1 implements List<Transform>
     return IterableMixinWorkaround.reduce(this, initialValue, combine);
   }
 
+  dynamic fold(dynamic initialValue, dynamic combine(dynamic, Transform)) {
+    return IterableMixinWorkaround.fold(this, initialValue, combine);
+  }
+
   bool contains(Transform element) => IterableMixinWorkaround.contains(this, element);
 
   void forEach(void f(Transform element)) => IterableMixinWorkaround.forEach(this, f);
@@ -8068,6 +8088,10 @@ class _ElementInstanceList extends NativeFieldWrapperClass1 implements List<Elem
     return IterableMixinWorkaround.reduce(this, initialValue, combine);
   }
 
+  dynamic fold(dynamic initialValue, dynamic combine(dynamic, ElementInstance)) {
+    return IterableMixinWorkaround.fold(this, initialValue, combine);
+  }
+
   bool contains(ElementInstance element) => IterableMixinWorkaround.contains(this, element);
 
   void forEach(void f(ElementInstance element)) => IterableMixinWorkaround.forEach(this, f);