Combine shelf platform and windowed app types.

ash/common/shelf/shelf_item_types.h

Index: ash/common/shelf/shelf_item_types.h
diff --git a/ash/common/shelf/shelf_item_types.h b/ash/common/shelf/shelf_item_types.h
index c09a06433649dd44bea3f47b2d39fa74e8b01551..2f05e8c5f60be906eb70d0da6a978ae0f486225d 100644
--- a/ash/common/shelf/shelf_item_types.h
+++ b/ash/common/shelf/shelf_item_types.h
@@ -30,11 +30,8 @@ enum ShelfItemType {
   // The browser shortcut button.
   TYPE_BROWSER_SHORTCUT,
 
-  // Represents a platform app.
-  TYPE_PLATFORM_APP,
-
-  // Represents a windowed V1 browser app.
-  TYPE_WINDOWED_APP,
+  // Represents an app (platform/V2 or windowed V1 browser).
+  TYPE_APP,

[Mr4D (OOO till 08-26), 2016/11/23 23:11:51]

We should probably name this TYPE_WEB_APP - or TYPE_BROWSER_APP.

Otherwise that gets confusing with the ARC_APP's and what else we will add next.

[msw, 2016/11/24 00:00:54]

I don't think we should add another item type for arc apps. My hope is to
simplify here first, then move things over to ShelfWindowWatcher, as I've
already done for panels. Some type differences should be expressible in other
ways, for example TYPE_APP_SHORTCUT is just TYPE_APP with STATUS_CLOSED. Context
menu items should be populated on the Extension/Arc side (which can still
discern the app type from the app id), and Chrome will have to interact with the
shelf more directly for V1 apps when they're opened as tabs, but otherwise I'd
like to minimize Chrome/Ash interaction, and knowledge of app types, etc. This
is still in the works, and I'm open to ideas, but I think reducing the set of
item types here makes more sense. WDYT?

[Mr4D (OOO till 08-26), 2016/11/24 02:21:33]

See longer eMail.

 
   // Represents a dialog.
   TYPE_DIALOG,