From e052d1f53776fe55a61460e5e754e0442f54ad1c Mon Sep 17 00:00:00 2001
From: Luke Chang <lchang@mozilla.com>
Date: Wed, 23 Aug 2017 17:35:32 +0800
Subject: [PATCH] Bug 1392975 - [Form Autofill] Avoid registering multiple
 listeners of DOMContentLoaded. r=seanlee

MozReview-Commit-ID: Eo3KSBoaotr

--HG--
extra : rebase_source : 7ef03e929e5e2320dd5ef692326c4fb31decd719
---
 .../formautofill/FormAutofillContent.jsm      | 27 ++++----
 .../formautofill/FormAutofillUtils.jsm        |  6 +-
 .../content/FormAutofillFrameScript.js        | 61 +++++++++++--------
 3 files changed, 50 insertions(+), 44 deletions(-)

diff --git a/browser/extensions/formautofill/FormAutofillContent.jsm b/browser/extensions/formautofill/FormAutofillContent.jsm
index 704518d26cef..dbffcf29e54e 100644
--- a/browser/extensions/formautofill/FormAutofillContent.jsm
+++ b/browser/extensions/formautofill/FormAutofillContent.jsm
@@ -480,11 +480,6 @@ var FormAutofillContent = {
       Services.cpmm.sendAsyncMessage("FormAutofill:InitStorage");
     }
 
-    if (!FormAutofillUtils.isFieldEligibleForAutofill(element)) {
-      this.log.debug("Not an eligible field.");
-      return;
-    }
-
     let formHandler = this.getFormHandler(element);
     if (!formHandler) {
       let formLike = FormLikeFactory.createFromField(element);
@@ -504,17 +499,7 @@ var FormAutofillContent = {
     );
   },
 
-  _markAsAutofillField(field) {
-    // Since Form Autofill popup is only for input element, any non-Input
-    // element should be excluded here.
-    if (!field || !(field instanceof Ci.nsIDOMHTMLInputElement)) {
-      return;
-    }
-
-    formFillController.markAsAutofillField(field);
-  },
-
-  _previewProfile(doc) {
+  previewProfile(doc) {
     let docWin = doc.ownerGlobal;
     let selectedIndex = ProfileAutocomplete._getSelectedIndex(docWin);
     let lastAutoCompleteResult = ProfileAutocomplete.getProfileAutoCompleteResult();
@@ -545,6 +530,16 @@ var FormAutofillContent = {
     }
   },
 
+  _markAsAutofillField(field) {
+    // Since Form Autofill popup is only for input element, any non-Input
+    // element should be excluded here.
+    if (!field || !(field instanceof Ci.nsIDOMHTMLInputElement)) {
+      return;
+    }
+
+    formFillController.markAsAutofillField(field);
+  },
+
   _messageManagerFromWindow(win) {
     return win.QueryInterface(Ci.nsIInterfaceRequestor)
               .getInterface(Ci.nsIWebNavigation)
diff --git a/browser/extensions/formautofill/FormAutofillUtils.jsm b/browser/extensions/formautofill/FormAutofillUtils.jsm
index 4a66ba40852c..4242fb0d2cb1 100644
--- a/browser/extensions/formautofill/FormAutofillUtils.jsm
+++ b/browser/extensions/formautofill/FormAutofillUtils.jsm
@@ -26,6 +26,7 @@ Cu.import("resource://gre/modules/Services.jsm");
 
 this.FormAutofillUtils = {
   get AUTOFILL_FIELDS_THRESHOLD() { return 3; },
+  get isAutofillEnabled() { return this.isAutofillAddressesEnabled || this.isAutofillCreditCardsEnabled; },
 
   ADDRESSES_COLLECTION_NAME,
   CREDITCARDS_COLLECTION_NAME,
@@ -141,12 +142,13 @@ this.FormAutofillUtils = {
       return false;
     }
 
-    if (element instanceof Ci.nsIDOMHTMLInputElement) {
+    let tagName = element.tagName;
+    if (tagName == "INPUT") {
       // `element.type` can be recognized as `text`, if it's missing or invalid.
       if (!this.ALLOWED_TYPES.includes(element.type)) {
         return false;
       }
-    } else if (!(element instanceof Ci.nsIDOMHTMLSelectElement)) {
+    } else if (tagName != "SELECT") {
       return false;
     }
 
diff --git a/browser/extensions/formautofill/content/FormAutofillFrameScript.js b/browser/extensions/formautofill/content/FormAutofillFrameScript.js
index 345b267338c6..364de7e95aba 100644
--- a/browser/extensions/formautofill/content/FormAutofillFrameScript.js
+++ b/browser/extensions/formautofill/content/FormAutofillFrameScript.js
@@ -12,8 +12,6 @@
 
 const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
 
-Cu.import("resource://gre/modules/Services.jsm");
-Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 Cu.import("resource://formautofill/FormAutofillContent.jsm");
 Cu.import("resource://formautofill/FormAutofillUtils.jsm");
 
@@ -23,6 +21,24 @@ Cu.import("resource://formautofill/FormAutofillUtils.jsm");
  * NOTE: Declares it by "var" to make it accessible in unit tests.
  */
 var FormAutofillFrameScript = {
+  _nextHandleElement: null,
+  _alreadyDOMContentLoaded: false,
+  _hasDOMContentLoadedHandler: false,
+  _hasPendingTask: false,
+
+  _doIdentifyAutofillFields() {
+    if (this._hasPendingTask) {
+      return;
+    }
+    this._hasPendingTask = true;
+
+    setTimeout(() => {
+      FormAutofillContent.identifyAutofillFields(this._nextHandleElement);
+      this._hasPendingTask = false;
+      this._nextHandleElement = null;
+    });
+  },
+
   init() {
     addEventListener("focusin", this);
     addMessageListener("FormAutofill:PreviewProfile", this);
@@ -31,40 +47,33 @@ var FormAutofillFrameScript = {
   },
 
   handleEvent(evt) {
-    if (!evt.isTrusted) {
+    if (!evt.isTrusted || !FormAutofillUtils.isAutofillEnabled) {
       return;
     }
 
-    if (!FormAutofillUtils.isAutofillAddressesEnabled &&
-        !FormAutofillUtils.isAutofillCreditCardsEnable) {
+    let element = evt.target;
+    if (!FormAutofillUtils.isFieldEligibleForAutofill(element)) {
       return;
     }
+    this._nextHandleElement = element;
 
-    switch (evt.type) {
-      case "focusin": {
-        let element = evt.target;
-        let doc = element.ownerDocument;
-
-        if (!FormAutofillUtils.isFieldEligibleForAutofill(element)) {
-          return;
+    if (!this._alreadyDOMContentLoaded) {
+      let doc = element.ownerDocument;
+      if (doc.readyState === "loading") {
+        if (!this._hasDOMContentLoadedHandler) {
+          this._hasDOMContentLoadedHandler = true;
+          doc.addEventListener("DOMContentLoaded", () => this._doIdentifyAutofillFields(), {once: true});
         }
-
-        let doIdentifyAutofillFields =
-          () => setTimeout(() => FormAutofillContent.identifyAutofillFields(element));
-
-        if (doc.readyState === "loading") {
-          doc.addEventListener("DOMContentLoaded", doIdentifyAutofillFields, {once: true});
-        } else {
-          doIdentifyAutofillFields();
-        }
-        break;
+        return;
       }
+      this._alreadyDOMContentLoaded = true;
     }
+
+    this._doIdentifyAutofillFields();
   },
 
   receiveMessage(message) {
-    if (!FormAutofillUtils.isAutofillAddressesEnabled &&
-        !FormAutofillUtils.isAutofillCreditCardsEnable) {
+    if (!FormAutofillUtils.isAutofillEnabled) {
       return;
     }
 
@@ -73,11 +82,11 @@ var FormAutofillFrameScript = {
 
     switch (message.name) {
       case "FormAutofill:PreviewProfile": {
-        FormAutofillContent._previewProfile(doc);
+        FormAutofillContent.previewProfile(doc);
         break;
       }
       case "FormAutoComplete:PopupClosed": {
-        FormAutofillContent._previewProfile(doc);
+        FormAutofillContent.previewProfile(doc);
         chromeEventHandler.removeEventListener("keydown", FormAutofillContent._onKeyDown,
                                                {capturing: true});
         break;