Implement initial chrome.browserAction.openPopup API.

chrome/common/extensions/api/_api_features.json

Index: chrome/common/extensions/api/_api_features.json
diff --git a/chrome/common/extensions/api/_api_features.json b/chrome/common/extensions/api/_api_features.json
index 8e58146f74dfed3c75f314e0fcfe624ee3f6857f..979f2dc6ea38133a4362dce306df1aeb6ceb0eff 100644
--- a/chrome/common/extensions/api/_api_features.json
+++ b/chrome/common/extensions/api/_api_features.json
@@ -102,8 +102,27 @@
   },
   "browserAction": {
     "dependencies": ["manifest:browser_action"],
-    "contexts": ["blessed_extension"]
+    "contexts": ["blessed_extension", "unblessed_extension"]
   },
+  // The following API enabled for dev pending resolution of security concerns.
+  // It is enabled for stable only for whitelisted extensions.
+  "browserAction.openPopup": [{
+    "channel": "dev",
+    "dependencies": ["manifest:browser_action"],
+    "contexts": ["blessed_extension"]
+  }, {
+    "channel": "stable",
+    "dependencies": ["manifest:browser_action"],
+    "whitelist": [
+      "enhhojjnijigcajfphajepfemndkmdlo",  // Dev
+      "pkedcjkdefgpdelpbcmbmeomcjbeemfm",  // Trusted Tester
+      "fmfcbgogabcbclcofgocippekhfcmgfj",  // Staging
+      "hfaagokkkhdbgiakmmlclaapfelnkoah",  // Canary
+      "F155646B5D1CA545F7E1E4E20D573DFDD44C2540",  // Trusted Tester (public)
+      "16CA7A47AAE4BE49B1E75A6B960C3875E945B264"   // Release
+    ],
+    "contexts": ["blessed_extension"]
+  }],
   "browsingData": {
     "dependencies": ["permission:browsingData"],
     "contexts": ["blessed_extension"]