Specs: Make it possible to import a module from a module or application by calling module.import(ur…

sky/specs/apis.md

 APIS
 ====
 
 The Sky core API
 ----------------
 
 ```javascript
 module 'sky:core' {
 
   // EVENTS
@@ skipping 154 matching lines @@
   }
   interface ImgElement : Element { }
   interface IframeElement : Element { }
   interface TElement : Element { }
   interface AElement : Element { }
   interface TitleElement : Element { }
 
 
 
   // MODULES
+  abstract interface AbstractModule : EventTarget {
+    Promise<any> import(String url); // O(Yikes) // returns the module's exports
+  }
 
-  interface Module : EventTarget {
+  interface Module : AbstractModule {
     constructor (Application application, Document document); // O(1)
     attribute any exports; // O(1) // defaults to the module's document
     readonly attribute Document document; // O(1) // the module's document
     readonly attribute Application application; // O(1)
   }
 
-  interface Application : EventTarget {
+  interface Application : AbstractModule {
     constructor (Document document); // O(1)
     attribute String title; // O(1)
     readonly attribute Document document; // O(1) // the application's document
   }
 
   // see script.md for a description of the global object, though note that
   // the sky core module doesn't use it or affect it in any way.
 
 }
 ```
@@ skipping 113 matching lines @@
 magical imports:
   the core mojo fabric JS API   sky:mojo:fabric:core
   the asyncWait/cancelWait mojo fabric JS API (interface to IPC thread)  sky:mojo:fabric:ipc
   the mojom for the shell, proxying through C++ so that the shell pipe isn't exposed  sky:mojo:shell
   the sky API  sky:core
 ```
 
 TODO(ianh): determine if we want to separate the "this" from the
 Document, especially for Modules, so that exposing a module's element
 doesn't expose the module's exports attribute.