Bug 1371888 - Stop having a sync IPC message to pass blocklist state, r=florian

Because plugin state in the content now contains blocklist state, and is updated
when the blocklist updates, we don't need to ask the parent if we're checking
blocklist state. All the consumers should now be asking the plugin code directly,
so we can stub out the last API here. We should look at removing the content side
of this service entirely, but that's something for a follow-up bug.

MozReview-Commit-ID: DE8s8RwT42r

--HG--
extra : rebase_source : 06fbc304e99679f55c7cdc52404cd138221feca3

toolkit/mozapps/extensions/nsBlocklistService.js

@@ -230,7 +230,6 @@ function Blocklist() {
   Services.prefs.addObserver(PREF_EM_LOGGING_ENABLED, this);
   this.wrappedJSObject = this;
   // requests from child processes come in here, see receiveMessage.
-  Services.ppmm.addMessageListener("Blocklist:getPluginBlocklistState", this);
   Services.ppmm.addMessageListener("Blocklist:content-blocklist-updated", this);
 }
 
@@ -256,7 +255,6 @@ Blocklist.prototype = {
 
   shutdown() {
     Services.obs.removeObserver(this, "xpcom-shutdown");
-    Services.ppmm.removeMessageListener("Blocklist:getPluginBlocklistState", this);
     Services.ppmm.removeMessageListener("Blocklist:content-blocklist-updated", this);
     Services.prefs.removeObserver("extensions.blocklist.", this);
     Services.prefs.removeObserver(PREF_EM_LOGGING_ENABLED, this);
@@ -294,10 +292,6 @@ Blocklist.prototype = {
   // Message manager message handlers
   receiveMessage(aMsg) {
     switch (aMsg.name) {
-      case "Blocklist:getPluginBlocklistState":
-        return this.getPluginBlocklistState(aMsg.data.addonData,
-                                            aMsg.data.appVersion,
-                                            aMsg.data.toolkitVersion);
       case "Blocklist:content-blocklist-updated":
         Services.obs.notifyObservers(null, "content-blocklist-updated");
         break;

toolkit/mozapps/extensions/nsBlocklistServiceContent.js

@@ -89,13 +89,8 @@ Blocklist.prototype = {
     return true;
   },
 
-  // There are a few callers in layout that rely on this.
   getPluginBlocklistState(aPluginTag, aAppVersion, aToolkitVersion) {
-    return Services.cpmm.sendSyncMessage("Blocklist:getPluginBlocklistState", {
-      addonData: this.flattenObject(aPluginTag),
-      appVersion: aAppVersion,
-      toolkitVersion: aToolkitVersion
-    })[0];
+    throw new Error(kMissingAPIMessage);
   },
 
   getAddonBlocklistURL(aAddon, aAppVersion, aToolkitVersion) {