Bug 1555438 - Add support to get appBuildID in RPM. r=johannh

Differential Revision: https://phabricator.services.mozilla.com/D33063

--HG--
extra : moz-landing-system : lando

toolkit/components/remotepagemanager/MessagePort.jsm

@@ -305,6 +305,14 @@ class MessagePort {
     return new this.window.Promise((resolve, reject) => promise.then(resolve, reject));
   }
 
+  getAppBuildID() {
+    let principal = this.window.document.nodePrincipal;
+    if (!RPMAccessManager.checkAllowAccess(principal, "getAppBuildID", "yes")) {
+      throw new Error("RPMAccessManager does not allow access to getAppBuildID");
+    }
+    return Services.appinfo.appBuildID;
+  }
+
   getIntPref(aPref) {
     let principal = this.window.document.nodePrincipal;
     if (!RPMAccessManager.checkAllowAccess(principal, "getIntPref", aPref)) {

toolkit/components/remotepagemanager/RemotePageManagerChild.jsm

@@ -29,6 +29,9 @@ class ChildMessagePort extends MessagePort {
       defineAs: "RPMRemoveMessageListener",
       allowCallbacks: true,
     });
+    Cu.exportFunction(this.getAppBuildID.bind(this), window, {
+      defineAs: "RPMGetAppBuildID",
+    });
     Cu.exportFunction(this.getIntPref.bind(this), window, {
       defineAs: "RPMGetIntPref",
     });

tools/lint/eslint/eslint-plugin-mozilla/lib/environments/frame-script.js

@@ -25,6 +25,7 @@ module.exports = {
     sendSyncMessage: false,
     sendRpcMessage: false,
     tabEventTarget: false,
+    RPMGetAppBuildID: false,
     RPMGetIntPref: false,
     RPMGetBoolPref: false,
     RPMSetBoolPref: false,