Specs: Make isNew only get set if it's not added in the same frame as the owner layout manager

sky/specs/style.md

 Sky Style Language
 ==================
 
 Planed changes
 --------------
 
 Add //-to-end-of-line comments to be consistent with the script
 language.
 
 
@@ skipping 251 matching lines @@
      |    |    +-- AnimatableStringStyleValue*
      |    |    
      |    +-- ObjectStyleValue
      |    
      +-- PrimitiveValuesListStyleValue*
 */
 ```
 
 The types marked with * in the list above are not part of sky:core.
 
+TODO(ianh): consider removing 'StyleValue' from these class names
+
 ```javascript
 abstract class StyleNode {
   abstract void markDirty();
 }
 
 class StyleValueResolverSettings {
   // this is used as an "out" parameter for 'resolve()' below
   constructor();
   void reset(); // resets values to defaults so that object can be reused
   attribute Boolean layoutDependent; // default to false
@@ skipping 37 matching lines @@
 abstract class LengthStyleValue : AbstractStyleValue {
   abstract Float resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
 }
 
 class PixelLengthStyleValue : LengthStyleValue {
   constructor(StyleNode parentNode, Float number);
   readonly attribute Float value;
   Float resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
 }
 
-typedef Color Float; // TODO(ianh): figure out what Color should be
+typedef RawColor Float; // TODO(ianh): figure out what Color should be
 class ColorStyleValue : LengthStyleValue {
   constructor(StyleNode parentNode, Float red, Float green, Float blue, Float alpha);
   // ... color API ...
-  Color resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
+  RawColor resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
 }
 
 class AbstractOpaqueStyleValue : AbstractStyleValue {
   abstract constructor(StyleNode parentNode, any value);
   readonly attribute any value;
   any resolve(PropertyHandle property, RenderNode node, StyleValueResolverSettings? settings = null);
     // returns value
 }
 
 class IdentifierStyleValue : AbstractOpaqueStyleValue {
@@ skipping 149 matching lines @@
 Cascade
 -------
 
 Simultaneously walk the tree rooted at the application Document,
 taking into account shadow trees and child distribution, and the tree
 rooted at the document's RenderNode.
 
 If you come across a node that doesn't have an assigned RenderNode,
 then create one, placing it in the appropriate place in the RenderTree
 tree, after any nodes marked isGhost=true, with ownerLayoutManager
-pointing to the parent RenderNode's layoutManager, and then, if
-autoreap is false on the ownerLayoutManager, mark it "isNew".
+pointing to the parent RenderNode's layoutManager, if it has one, and,
+if it has one and autoreap is false on that layout manager, mark the
+new node "isNew". (This means that when a node is marked isNew, the
+layout manager has already laid out at least one frame.)
 
 For each element, if the node's needsManager is true, call
 getLayoutManager() on the element, and if that's not null, and if the
 returned class isn't the same class as the current layoutManager, if
 any, construct the given class and assign it to the RenderNode's
 layoutManager, then set all the child RenderNodes' ownerLayoutManager
 to that object; if it returns null, and that node already has a
 layoutManager, then set isGhost=true for that node and all its
 children (without changing the layoutManager). Otherwise, if it
 returned null and there's already no layoutManager, remove the node
@@ skipping 409 matching lines @@
 ```
 
 The ``div`` element doesn't have any default styles.
 
 These declarations are all shared between all the elements (so e.g. if
 you reach in and change the declaration that was added to a ``title``
 element, you're going to change the styles of all the other
 default-hidden elements). (In other words, in the code snippets above,
 the ``d`` variable is initialised in shared code, and only the
 addStyles() call is per-element.)