Change how we provide value previews in the vm service.

runtime/bin/vmservice/client/lib/src/elements/instance_ref.html

Index: runtime/bin/vmservice/client/lib/src/elements/instance_ref.html
diff --git a/runtime/bin/vmservice/client/lib/src/elements/instance_ref.html b/runtime/bin/vmservice/client/lib/src/elements/instance_ref.html
index 26b5d54ff480149338c6aeab5e676d9693b431ce..d061d8b1126ab5737571808482e0cea8d996129c 100644
--- a/runtime/bin/vmservice/client/lib/src/elements/instance_ref.html
+++ b/runtime/bin/vmservice/client/lib/src/elements/instance_ref.html
@@ -29,14 +29,14 @@
       </template>
 
       <template if="{{ isNull(ref.serviceType) }}">
-        <div title="{{ hoverText }}">{{ ref['preview'] }}</div>
+        <div title="{{ hoverText }}">{{ ref['valueAsString'] }}</div>
       </template>
 
       <template if="{{ (isString(ref.serviceType) ||
                         isBool(ref.serviceType) ||
                         isInt(ref.serviceType)) ||
                         isDouble(ref.serviceType)) }}">
-        <a href="{{ url }}">{{ ref['preview'] }}</a>
+        <a href="{{ url }}">{{ ref['valueAsString'] }}</a>
       </template>
 
       <template if="{{ (isType(ref.serviceType)) }}">