Bug 1574487 - Remove loadstart and loadend event from <img>, r=edgar

Depends on D159930

Differential Revision: https://phabricator.services.mozilla.com/D159931

dom/base/nsImageLoadingContent.cpp

@@ -252,15 +252,8 @@ void nsImageLoadingContent::OnLoadComplete(imgIRequest* aRequest,
   // Fire the appropriate DOM event.
   if (NS_SUCCEEDED(aStatus)) {
     FireEvent(u"load"_ns);
-
-    // Do not fire loadend event for multipart/x-mixed-replace image streams.
-    bool isMultipart;
-    if (NS_FAILED(aRequest->GetMultipart(&isMultipart)) || !isMultipart) {
-      FireEvent(u"loadend"_ns);
-    }
   } else {
     FireEvent(u"error"_ns);
-    FireEvent(u"loadend"_ns);
   }
 
   SVGObserverUtils::InvalidateDirectRenderingObservers(
@@ -987,7 +980,6 @@ nsImageLoadingContent::LoadImageWithChannel(nsIChannel* aChannel,
   if (!mCurrentRequest) aChannel->GetURI(getter_AddRefs(mCurrentURI));
 
   FireEvent(u"error"_ns);
-  FireEvent(u"loadend"_ns);
   return rv;
 }
 
@@ -1063,14 +1055,10 @@ nsresult nsImageLoadingContent::LoadImage(nsIURI* aNewURI, bool aForce,
     return NS_OK;
   }
 
-  // Fire loadstart event if required
-  FireEvent(u"loadstart"_ns);
-
   if (!mLoadingEnabled) {
     // XXX Why fire an error here? seems like the callers to SetLoadingEnabled
     // don't want/need it.
     FireEvent(u"error"_ns);
-    FireEvent(u"loadend"_ns);
     return NS_OK;
   }
 
@@ -1100,7 +1088,6 @@ nsresult nsImageLoadingContent::LoadImage(nsIURI* aNewURI, bool aForce,
     ClearPendingRequest(NS_BINDING_ABORTED, Some(OnNonvisible::DiscardImages));
 
     FireEvent(u"error"_ns);
-    FireEvent(u"loadend"_ns);
     return NS_OK;
   }
 
@@ -1207,7 +1194,6 @@ nsresult nsImageLoadingContent::LoadImage(nsIURI* aNewURI, bool aForce,
     }
 
     FireEvent(u"error"_ns);
-    FireEvent(u"loadend"_ns);
   }
 
   return NS_OK;

dom/base/nsImageLoadingContent.h

@@ -356,8 +356,7 @@ class nsImageLoadingContent : public nsIImageLoadingContent {
   /**
    * Method to fire an event once we know what's going on with the image load.
    *
-   * @param aEventType "loadstart", "loadend", "load", or "error" depending on
-   *                   how things went
+   * @param aEventType "load", or "error" depending on how things went
    * @param aIsCancelable true if event is cancelable.
    */
   nsresult FireEvent(const nsAString& aEventType, bool aIsCancelable = false);

dom/tests/mochitest/general/test_interfaces.js

@@ -1618,8 +1618,6 @@ let interfaceNamesInGlobalScope = [
   // IMPORTANT: Do not change this list without review from a DOM peer!
   { name: "onloadedmetadata", insecureContext: true },
   // IMPORTANT: Do not change this list without review from a DOM peer!
-  { name: "onloadend", insecureContext: true },
-  // IMPORTANT: Do not change this list without review from a DOM peer!
   { name: "onloadstart", insecureContext: true },
   // IMPORTANT: Do not change this list without review from a DOM peer!
   { name: "onlostpointercapture", insecureContext: true },

dom/webidl/EventHandler.webidl

@@ -62,7 +62,6 @@ interface mixin GlobalEventHandlers {
            attribute EventHandler onload;
            attribute EventHandler onloadeddata;
            attribute EventHandler onloadedmetadata;
-           attribute EventHandler onloadend;
            attribute EventHandler onloadstart;
            attribute EventHandler onmousedown;
   [LegacyLenientThis] attribute EventHandler onmouseenter;

testing/web-platform/meta/html/semantics/embedded-content/the-img-element/historical-progress-event.window.js.ini

@@ -1,7 +0,0 @@
-[historical-progress-event.window.html]
-  [onloadend is not exposed]
-    expected: FAIL
-
-  [<img> does not support ProgressEvent or loadstart/progress/loadend]
-    expected: FAIL
-

toolkit/components/antitracking/test/browser/browser_staticPartition_saveAs.js

@@ -423,7 +423,7 @@ add_task(async function testPageInfoMediaSaveAs() {
         let preview = pageInfo.document.getElementById("thepreviewimage");
         let mediaType = pageInfo.gImageView.data[i][1]; // COL_IMAGE_TYPE
         if (mediaType == "Image") {
-          await BrowserTestUtils.waitForEvent(preview, "loadend");
+          await BrowserTestUtils.waitForEvent(preview, "load");
         } else if (mediaType == "Video") {
           await BrowserTestUtils.waitForEvent(preview, "canplaythrough");
         }