Addition of 'maxSize' to experimental popup extension API.

chrome/common/extensions/api/extension_api.json

 [
   {
     "namespace": "extension",
     "unprivileged": true,
     "types": [
       {
         "id": "MessageSender",
         "type": "object",
         "description": "An object containing information about the script context that sent a message or request.",
         "properties": {
@@ skipping 2324 matching lines @@
               "giveFocus": {
                 "type": "boolean",
                 "description": "Pass true to give the focus to the popup window.  The default behaviour is true.",
                 "optional": true
               },
               "borderStyle": {
                 "type": "string",
                 "description": "Pass 'bubble' to give the pop-up window a bubble-chrome border, including an arrow pointing at the relative-to point.  Pass 'rectangle' to give the pop-up a rectangular black border with drop-shadow.  Default behaviour is to pass 'bubble'.",
                 "optional": true,
                 "enum": ["bubble", "rectangle"]
+              },
+              "maxSize": {
+                "type": "object",
+                "optional": true,
+                "properties": {
+                  "width": {
+                    "type": "integer",
+                    "description": "The maximal width to which the popup will resize.  If not present, the popup will be no wider than 800 pixels.  The popup will widen to no larger than the minimum of the width parameter and the width of the screen.",
+                    "optional": true,
+                    "minimum": 32
+                  },
+                  "height": {
+                    "type": "integer",
+                    "description": "The maximal height to which the popup will resize.  If not present, the popup will be no taller than 600 pixels.  The popup will grow to no taller than than the minimum of the height parameter and the width of the screen.",
+                    "optional": true,
+                    "minimum": 32
+                  }
+                }
               }
             }
           },
           {
             "type": "function",
             "name": "callback",
             "optional": true,
             "parameters": []
           }
         ]
@@ skipping 2011 matching lines @@
                   "token": { "type": "string", "optional": true }
                 }
               }
             ]
           }
         ]
       }
     ]
   }
 ]