Bug 1474143 - Remove unused 'firstformsubmit' category and gFirstFormSubmitted. r=Ehsan

Differential Revision: https://phabricator.services.mozilla.com/D16650

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

dom/html/HTMLFormElement.cpp

@@ -92,8 +92,6 @@ static const nsAttrValue::EnumTable kFormAutocompleteTable[] = {
 static const nsAttrValue::EnumTable* kFormDefaultAutocomplete =
     &kFormAutocompleteTable[0];
 
-bool HTMLFormElement::gFirstFormSubmitted = false;
-
 HTMLFormElement::HTMLFormElement(
     already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
     : nsGenericHTMLElement(std::move(aNodeInfo)),
@@ -852,14 +850,6 @@ nsresult HTMLFormElement::DoSecureToInsecureSubmitCheck(nsIURI* aActionURL,
 nsresult HTMLFormElement::NotifySubmitObservers(nsIURI* aActionURL,
                                                 bool* aCancelSubmit,
                                                 bool aEarlyNotify) {
-  // If this is the first form, bring alive the first form submit
-  // category observers
-  if (!gFirstFormSubmitted) {
-    gFirstFormSubmitted = true;
-    NS_CreateServicesFromCategory(NS_FIRST_FORMSUBMIT_CATEGORY, nullptr,
-                                  NS_FIRST_FORMSUBMIT_CATEGORY);
-  }
-
   if (!aEarlyNotify) {
     nsresult rv = DoSecureToInsecureSubmitCheck(aActionURL, aCancelSubmit);
     if (NS_FAILED(rv)) {

dom/html/HTMLFormElement.h

@@ -602,10 +602,6 @@ class HTMLFormElement final : public nsGenericHTMLElement,
    */
   bool mEverTriedInvalidSubmit;
 
- protected:
-  /** Detection of first form to notify observers */
-  static bool gFirstFormSubmitted;
-
  private:
   ~HTMLFormElement();
 };

dom/html/nsIFormSubmitObserver.idl

@@ -25,6 +25,5 @@ interface nsIFormSubmitObserver: nsISupports
 %{C++
 #define NS_FORMSUBMIT_SUBJECT "formsubmit"
 #define NS_EARLYFORMSUBMIT_SUBJECT "earlyformsubmit"
-#define NS_FIRST_FORMSUBMIT_CATEGORY "firstformsubmit"
 #define NS_INVALIDFORMSUBMIT_SUBJECT "invalidformsubmit"
 %}