Elim detached_panel type and update chrome.windows documentation

tools/json_schema_compiler/test/windows.json

 [
   {
     "namespace": "windows",
     "description": "The windows API.",
     "types": [
       {
         "id": "Window",
         "type": "object",
         "properties": {
           "id": {"type": "integer", "minimum": 0, "description": "The ID of the window. Window IDs are unique within a browser session."},
@@ skipping 148 matching lines @@
               "tabId": {"type": "integer", "minimum": 0, "optional": true, "description": "The id of the tab for which you want to adopt to the new window."},
               "left": {"type": "integer", "optional": true, "description": "The number of pixels to position the new window from the left edge of the screen. If not specified, the new window is offset naturally from the last focusd window. This value is ignored for panels."},
               "top": {"type": "integer", "optional": true, "description": "The number of pixels to position the new window from the top edge of the screen. If not specified, the new window is offset naturally from the last focusd window. This value is ignored for panels."},
               "width": {"type": "integer", "minimum": 0, "optional": true, "description": "The width in pixels of the new window. If not specified defaults to a natural width."},
               "height": {"type": "integer", "minimum": 0, "optional": true, "description": "The height in pixels of the new window. If not specified defaults to a natural height."},
               "focused": {"type": "boolean", "optional": true, "description": "If true, opens an active window. If false, opens an inactive window."},
               "incognito": {"type": "boolean", "optional": true, "description": "Whether the new window should be an incognito window."},
               "type": {
                 "type": "string",
                 "optional": true,
-                "description": "Specifies what type of browser window to create. The 'panel' type creates a popup unless the '--enable-panels' flag is set.",
+                "description": "Specifies what type of browser window to create.",
                 "enum": ["normal", "popup", "panel"]
               }
             },
             "optional": true
           },
           {
             "type": "function",
             "name": "callback",
             "optional": true,
             "parameters": [
@@ skipping 76 matching lines @@
         "name": "onFocusChanged",
         "type": "function",
         "description": "Fired when the currently focused window changes. Will be chrome.windows.WINDOW_ID_NONE if all chrome windows have lost focus. Note: On some Linux window managers, WINDOW_ID_NONE will always be sent immediately preceding a switch from one chrome window to another.",
         "parameters": [
           {"type": "integer", "name": "windowId", "minimum": -1, "description": "ID of the newly focused window."}
         ]
       }
     ]
   }
 ]