Bug 1566215 - Part 4: Use message manager to send layout debugger commands to content. r=dbaron

Differential Revision: https://phabricator.services.mozilla.com/D38414

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

layout/tools/layout-debug/ui/content/layoutdebug-helper.js

@@ -0,0 +1,19 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Frame script that runs in the layout debugger's <browser>.
+
+var gDebuggingTools;
+
+const NS_LAYOUT_DEBUGGINGTOOLS_CONTRACTID =
+  "@mozilla.org/layout-debug/layout-debuggingtools;1";
+
+gDebuggingTools = Cc[NS_LAYOUT_DEBUGGINGTOOLS_CONTRACTID].createInstance(
+  Ci.nsILayoutDebuggingTools
+);
+gDebuggingTools.init(content);
+
+addMessageListener("LayoutDebug:Call", function(msg) {
+  gDebuggingTools[msg.data.name](msg.data.arg);
+});

layout/tools/layout-debug/ui/content/layoutdebug.js

@@ -11,8 +11,7 @@ const { Preferences } = ChromeUtils.import(
 );
 const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
 
-const NS_LAYOUT_DEBUGGINGTOOLS_CONTRACTID =
-  "@mozilla.org/layout-debug/layout-debuggingtools;1";
+const HELPER_URL = "chrome://layoutdebug/content/layoutdebug-helper.js";
 
 const FEATURES = {
   paintFlashing: "nglayout.debug.paint_flashing",
@@ -40,14 +39,11 @@ class Debugger {
     this._flags = new Map();
     this._visualDebugging = false;
     this._visualEventDebugging = false;
-    this._tools = Cc[NS_LAYOUT_DEBUGGINGTOOLS_CONTRACTID].createInstance(
-      Ci.nsILayoutDebuggingTools
-    );
 
     for (let [name, pref] of Object.entries(FEATURES)) {
       this._flags.set(name, !!Preferences.get(pref, false));
     }
-    this._tools.init(gBrowser.contentWindow);
+    gBrowser.messageManager.loadFrameScript(HELPER_URL, false);
   }
 
   get visualDebugging() {
@@ -57,7 +53,7 @@ class Debugger {
   set visualDebugging(v) {
     v = !!v;
     this._visualDebugging = v;
-    this._tools.setVisualDebugging(v);
+    this._sendMessage("setVisualDebugging", v);
   }
 
   get visualEventDebugging() {
@@ -67,7 +63,11 @@ class Debugger {
   set visualEventDebugging(v) {
     v = !!v;
     this._visualEventDebugging = v;
-    this._tools.setVisualEventDebugging(v);
+    this._sendMessage("setVisualEventDebugging", v);
+  }
+
+  _sendMessage(name, arg) {
+    gBrowser.messageManager.sendAsyncMessage("LayoutDebug:Call", { name, arg });
   }
 }
 
@@ -82,16 +82,16 @@ for (let [name, pref] of Object.entries(FEATURES)) {
       this._flags.set(name, v);
       // XXX PresShell should watch for this pref change itself.
       if (name == "reflowCounts") {
-        this._tools.setReflowCounts(v);
+        this._sendMessage("setReflowCounts", v);
       }
-      this._tools.forceRefresh();
+      this._sendMessage("forceRefresh");
     },
   });
 }
 
 for (let name of COMMANDS) {
   Debugger.prototype[name] = function() {
-    this._tools[name]();
+    this._sendMessage(name);
   };
 }
 

layout/tools/layout-debug/ui/jar.mn

@@ -7,4 +7,5 @@ layoutdebug.jar:
 % locale layoutdebug en-US %locale/en-US/layoutdebug/
   content/layoutdebug/layoutdebug.xul              (content/layoutdebug.xul)
   content/layoutdebug/layoutdebug.js               (content/layoutdebug.js)
+  content/layoutdebug/layoutdebug-helper.js        (content/layoutdebug-helper.js)
   locale/en-US/layoutdebug/layoutdebug.dtd         (locale/en-US/layoutdebug.dtd)