Add SetImageData api to chrome.clipboard.

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 chrome/common/extensions/api/_features.md to understand this file, as
 // well as feature.h, simple_feature.h, and base_feature_provider.h.
 
 // If you add a new platform_app permission please update the "stubs_app" test:
@@ skipping 134 matching lines @@
       "96FF2FFA5C9173C76D47184B3E86D267B37781DE",  // http://crbug.com/642141
       "0136FCB13DB29FD5CD442F56E59E53B61F1DF96F"   // http://crbug.com/642141
     ]
   },
   "clipboardRead": {
     "channel": "stable",
     "extension_types": [
       "extension", "legacy_packaged_app", "hosted_app", "platform_app"
     ]
   },
+  "clipboardReadWrite": {
+    "channel": "dev",
+    "extension_types": [
+      "extension", "legacy_packaged_app", "hosted_app", "platform_app"
+    ]
+  },  
   "clipboardWrite": {
     "channel": "stable",
     "extension_types": [
       "extension", "legacy_packaged_app", "hosted_app", "platform_app"
     ]
   },
   "cloudPrintPrivate": {
     "channel": "stable",
     "extension_types": ["extension", "legacy_packaged_app", "hosted_app"],
     // CloudPrint
@@ skipping 777 matching lines @@
     "channel": "stable",
     "extension_types": ["platform_app"],
     "platforms": ["chromeos"],
     "whitelist": [
       "A948368FC53BE437A55FEB414106E207925482F5",  // Files app
       "8C726564C6DBE7380BAB388DE6CC7EC93EB44B06",  // Video player
       "5065C83E84321221675D20FBE4DC43C655CC8C6F"   // Files app tests
     ]
   }
 }