Make launcherSearchProvider API white-listed on stable and public on dev.

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.
 
 // This features file defines permissions for extension APIs implemented
 // under src/chrome.
 // See extensions/common/features/* to understand this file, in particular
 // feature.h, simple_feature.h, and base_feature_provider.h.
 
 // To add a new whitelisted ID, SHA-1 it and force it to uppercase. In Bash:
@@ skipping 520 matching lines @@
       "2462D64ACB971A7E708757159C2B17761D4FF54A",  // Citrix Receiver
       "3010EF507AFEF487EEA9CDE2930EC94867C60936",  // Citrix Receiver Beta
       "ABAABC5F49E022A76CBB12972A53B58354C04AC6"   // Citrix Receiver Dev
     ]
   },{
     "channel": "stable",
     "extension_types": ["extension", "legacy_packaged_app", "platform_app"],
     "location": "component"
   }],
   "launcherSearchProvider": {
-    "channel": "dev",
+    "channel": "stable",
     "extension_types": ["extension", "platform_app"],
     "platform": ["chromeos"],
     "whitelist": [
       "A948368FC53BE437A55FEB414106E207925482F5"  // File Manager
     ]
   },
   "location": [
     {
       "channel": "dev",
       "extension_types": [
@@ skipping 466 matching lines @@
     "channel": "stable",
     "extension_types": ["platform_app"],
     "platforms": ["chromeos"],
     "whitelist": [
       "A948368FC53BE437A55FEB414106E207925482F5",  // Files app
       "8C726564C6DBE7380BAB388DE6CC7EC93EB44B06",  // Video player
       "5065C83E84321221675D20FBE4DC43C655CC8C6F"   // Files app tests
     ]
   }
 }