Introduce a stable set of errors for inline install

chrome/common/extensions/api/webstore.json

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 [
   {
     "namespace": "webstore",
     "description": "Use the <code>chrome.webstore</code> API to initiate app and extension installations \"inline\" from your site.",
     "types": [
       {
         "id": "InstallStage",
         "type": "string",
         "enum": ["installing", "downloading"],
         "description": "Enum used to indicate the stage of the installation process. 'downloading' indicates that the necessary files are being downloaded, and 'installing' indicates that the files are downloaded and are being actively installed."
+      },
+      {
+        "id": "ErrorCode",
+        "type": "string",
+        "description": "Enum of the possible install results, including error codes sent back in the event that an inline installation has failed.",
+        "enum": [
+          // Keep this list of enums in sync with
+          // chrome/common/extensions/webstore_install_result.h and
+          // chrome/common/extensions/api/webstore/webstore_api_constants.cc!
+          {
+            "description": "An uncommon, unrecognized, or unexpected error. In some cases, the readable error string can provide more information.",
+            "name": "otherError"
+          },
+          {
+            "description": "The operation was aborted as the requestor is no longer alive.",
+            "name": "aborted"
+          },
+          {
+            "description": "An installation of the same extension is in progress.",
+            "name": "installInProgress"
+          },
+          {
+            "description": "The installation is not permitted.",
+            "name": "notPermitted"
+          },
+          {
+            "description": "Invalid Chrome Web Store item ID.",
+            "name": "invalidId"
+          },
+          {
+            "description": "Failed to retrieve extension metadata from the Web Store.",
+            "name": "webstoreRequestError"
+          },
+          {
+            "description": "The extension metadata retrieved from the Web Store was invalid.",
+            "name": "invalidWebstoreResponse"
+          },
+          {
+            "description": "An error occurred while parsing the extension manifest retrieved from the Web Store.",
+            "name": "invalidManifest"
+          },
+          {
+            "description": "Failed to retrieve the extension's icon from the Web Store, or the icon was invalid.",
+            "name": "iconError"
+          },
+          {
+            "description": "The user canceled the operation.",
+            "name": "userCanceled"
+          },
+          {
+            "description": "The extension is blacklisted.",
+            "name": "blacklisted"
+          },
+          {
+            "description": "Unsatisfied dependencies, such as shared modules.",
+            "name": "missingDependencies"
+          },
+          {
+            "description": "Unsatisfied requirements, such as webgl.",
+            "name": "requirementViolations"
+          },
+          {
+            "description": "The extension is blocked by management policies.",
+            "name": "blockedByPolicy"
+          },
+          {
+            "description": "The launch feature is not available.",
+            "name": "launchFeatureDisabled"

[tmdiep, 2014/07/25 00:45:04]

I saw this patch while merging.

These error codes are shared by the EphemeralAppLauncher and
WebstoreStandaloneInstaller, so there are a couple that will not occur for
inline installs:
- launchFeatureDisabled
- launchUnsupportedExtensionType
I think we should exclude these from this interface.

+          },
+          {
+            "description": "The launch feature is not supported for the extension type.",
+            "name": "launchUnsupportedExtensionType"
+          },
+          {
+            "description": "A launch of the same extension is in progress.",
+            "name": " launchInProgress"
+          }
+        ]
       }
     ],  // types
     "events": [
       {
         "name": "onInstallStageChanged",
         "description": "Fired when an inline installation enters a new InstallStage. In order to receive notifications about this event, listeners must be registered before the inline installation begins.",
         "type": "function",
         "parameters": [
           {
             "name": "stage",
@@ skipping 35 matching lines @@
           },
           {
             "name": "failureCallback",
             "type": "function",
             "optional": true,
             "parameters": [
               {
                 "name": "error",
                 "type": "string",
                 "description": "The failure detail. You may wish to inspect or log this for debugging purposes, but you should not rely on specific strings being passed back."
+              },
+              {
+                "name": "errorCode",
+                "$ref": "ErrorCode",
+                "optional": "true",
+                "description": "The error code from the stable set of possible errors."
               }
             ],
             "description": "This function is invoked when inline installation does not successfully complete. Possible reasons for this include the user canceling the dialog, the linked item not being found in the store, or the install being initiated from a non-verified site."
           }
         ]
       }  // install
     ]  // functions
   }  // webstore
 ]