[SystemInfo API] Move Storage API out of experimental namespace and rename to the "system" namespace

chrome/common/extensions/api/_permission_features.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.
 
 // See c/c/e/features/* to understand this file, in particular feature.h,
 // simple_feature.h, and base_feature_provider.h.
 
 {
   "activeTab": {
     "channel": "stable",
@@ skipping 521 matching lines @@
     ],
     "whitelist": [""]
   },
   "systemInfo.memory": {
     "channel": "dev",
     "extension_types": [
       "extension", "packaged_app", "hosted_app", "platform_app"
     ],
     "whitelist": [""]
   },
+  "system.storage": {
+    "channel": "stable",
+    "extension_types": [
+      "extension", "packaged_app", "hosted_app", "platform_app"
+    ]
+  },
+  "system.storage.addAvailableCapacityWatch": {
+    "channel": "dev",
+    "extension_types": [
+      "extension", "packaged_app", "hosted_app", "platform_app"
+    ]
+  },
+  "system.storage.removeAvailableCapacityWatch": {
+    "channel": "dev",
+    "extension_types": [
+      "extension", "packaged_app", "hosted_app", "platform_app"
+    ]
+  },
+  "system.storage.getAllAvailableCapacityWatches": {
+    "channel": "dev",
+    "extension_types": [
+      "extension", "packaged_app", "hosted_app", "platform_app"
+    ]
+  },
+  "system.storage.removeAllAvailableCapacityWatches": {
+    "channel": "dev",
+    "extension_types": [
+      "extension", "packaged_app", "hosted_app", "platform_app"
+    ]
+  },
+  "system.storage.onAvailableCapacityChanged": {
+    "channel": "dev",
+    "extension_types": [
+      "extension", "packaged_app", "hosted_app", "platform_app"
+    ]
+  },

[Haojian Wu, 2013/07/18 08:51:20]

I'm not sure whether this is the right way to make storage related
AvailableCapacity APIs only in dev channel since I don't find any other similar
API examples to follow. Please correct me if I'm wrong.

BTW, how to test these APIs under different channel(dev/stable)?

[Hongbo Min, 2013/07/18 09:56:43]

I think you are right.

Testing the api in dev channel is the same as current approach, writing apitest
and run browsertest since you are building on trunk.

Dev channel is generally behind trunk about 1~2 weeks 

[Haojian Wu, 2013/07/18 10:44:30]

That means we can only build the trunk-channel chromium on our local machine?

So now we can not test these related Storage APIs whether are available on
dev/stable channel, right? 

[方觉(Fang Jue), 2013/07/18 11:44:30]

No. This will not make these methods dev only. _permission_features.json only
contains permissions. _api_features.json can contain API methods but can only
restrict them to specific contexts but not specific channels. Probably you
should ask kalman about this. I think it's a common case to add new experimental
API within existing namespaces.

To make only those methods restricted to dev channel, you probably have to do it
in C++ implementation. Here's an example in the web request API in the past:
https://chromiumcodereview.appspot.com/12077029/diff/1/chrome/browser/extensi....

[Haojian Wu, 2013/07/18 15:43:31]

Thanks for the useful instructions and link.

kalman@, Do we need to restrict these APIs in C++ implementation? 

[not at google - send to devlin, 2013/07/18 17:06:18]

This is almost correct, you don't need to restrict in C++, you can do it via
features.

However this per-API-call thing should be done in _api_features not here. See
the various runtime.* methods.

[Haojian Wu, 2013/07/19 08:47:12]

Done. Please check whether I get your point.

   "systemInfo.display": {
     "channel": "stable",
     "extension_types": ["extension", "packaged_app", "platform_app"]
   },
   "systemPrivate": {
     "channel": "stable",
     "extension_types": ["extension", "packaged_app"],
     "location": "component"
   },
   "tabs": {
@@ skipping 86 matching lines @@
   },
   "webRequestBlocking": {
     "channel": "stable",
     "extension_types": ["extension", "packaged_app"]
   },
   "webview": {
     "channel": "stable",
     "extension_types": ["platform_app"]
   }
 }