Make html lists print a nice toString method.

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 a665e68dc8f78cb6ece33f6dd0ed94dee4d16655..64ddcde0992d7604546bed7d898709109442bacc 100644
--- a/sdk/lib/svg/dartium/svg_dartium.dart
+++ b/sdk/lib/svg/dartium/svg_dartium.dart
@@ -3505,6 +3505,13 @@ class LengthList extends NativeFieldWrapperClass1 implements List<Length> {
   Map<int, Length> asMap() =>
     IterableMixinWorkaround.asMapList(this);
 
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
+
   // -- end List<Length> mixins.
 
   @DomName('SVGLengthList.appendItem')
@@ -4220,6 +4227,13 @@ class NumberList extends NativeFieldWrapperClass1 implements List<Number> {
   Map<int, Number> asMap() =>
     IterableMixinWorkaround.asMapList(this);
 
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
+
   // -- end List<Number> mixins.
 
   @DomName('SVGNumberList.appendItem')
@@ -5411,6 +5425,13 @@ class PathSegList extends NativeFieldWrapperClass1 implements List<PathSeg> {
   Map<int, PathSeg> asMap() =>
     IterableMixinWorkaround.asMapList(this);
 
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
+
   // -- end List<PathSeg> mixins.
 
   @DomName('SVGPathSegList.appendItem')
@@ -6407,6 +6428,13 @@ class StringList extends NativeFieldWrapperClass1 implements List<String> {
   Map<int, String> asMap() =>
     IterableMixinWorkaround.asMapList(this);
 
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
+
   // -- end List<String> mixins.
 
   @DomName('SVGStringList.appendItem')
@@ -7672,6 +7700,13 @@ class TransformList extends NativeFieldWrapperClass1 implements List<Transform>
   Map<int, Transform> asMap() =>
     IterableMixinWorkaround.asMapList(this);
 
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
+
   // -- end List<Transform> mixins.
 
   @DomName('SVGTransformList.appendItem')
@@ -8259,6 +8294,13 @@ class _ElementInstanceList extends NativeFieldWrapperClass1 implements List<Elem
   Map<int, ElementInstance> asMap() =>
     IterableMixinWorkaround.asMapList(this);
 
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
+
   // -- end List<ElementInstance> mixins.
 
   @DomName('SVGElementInstanceList.item')