From a444b5cc390cbf522671e7a3f7c35fb4cadd3bb0 Mon Sep 17 00:00:00 2001
From: Moonchild <moonchild@palemoon.org>
Date: Tue, 12 May 2020 18:28:25 +0000
Subject: Issue #1543 - Follow-up: avoid displaying the Alt text if an image is
 loading.

This prevents the Alt text from briefly being shown before being replaced
with the image.
---
 layout/generic/nsImageFrame.cpp | 26 +++++++++-----------------
 layout/style/res/html.css       |  1 -
 2 files changed, 9 insertions(+), 18 deletions(-)

diff --git a/layout/generic/nsImageFrame.cpp b/layout/generic/nsImageFrame.cpp
index 226cca2cf..03fcbd8e3 100644
--- a/layout/generic/nsImageFrame.cpp
+++ b/layout/generic/nsImageFrame.cpp
@@ -430,15 +430,11 @@ nsImageFrame::SourceRectToDest(const nsIntRect& aRect)
 // that we'll construct image frames for them as needed if their display is
 // toggled from "none" (though we won't paint them, unless their visibility
 // is changed too).
-#define BAD_STATES (NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_USERDISABLED | \
-                    NS_EVENT_STATE_LOADING)
+#define BAD_STATES (NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_USERDISABLED)
 
-// This is a macro so that we don't evaluate the boolean last arg
-// unless we have to; it can be expensive
-#define IMAGE_OK(_state, _loadingOK)                                           \
-   (!(_state).HasAtLeastOneOfStates(BAD_STATES) ||                                    \
-    (!(_state).HasAtLeastOneOfStates(NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_USERDISABLED) && \
-     (_state).HasState(NS_EVENT_STATE_LOADING) && (_loadingOK)))
+static bool ImageOk(EventStates aState) {
+  return !aState.HasAtLeastOneOfStates(BAD_STATES);
+}
 
 static bool HasAltText(Element* aElement)
 {
@@ -459,10 +455,8 @@ static bool HasAltText(Element* aElement)
 nsImageFrame::ShouldCreateImageFrameFor(Element* aElement,
                                         nsStyleContext* aStyleContext)
 {
-  EventStates state = aElement->State();
-  if (IMAGE_OK(state,
-               HaveSpecifiedSize(aStyleContext->StylePosition()))) {
-    // Image is fine; do the image frame thing
+  if (ImageOk(aElement->State())) {
+    // Image is fine or loading; do the image frame thing
     return true;
   }
 
@@ -1016,8 +1010,7 @@ nsImageFrame::Reflow(nsPresContext*          aPresContext,
   }
 
   aMetrics.SetOverflowAreasToDesiredBounds();
-  EventStates contentState = mContent->AsElement()->State();
-  bool imageOK = IMAGE_OK(contentState, true);
+  bool imageOK = ImageOk(mContent->AsElement()->State());
 
   // Determine if the size is available
   bool haveSize = false;
@@ -1336,7 +1329,7 @@ nsImageFrame::DisplayAltFeedback(nsRenderingContext& aRenderingContext,
   MOZ_ASSERT(gIconLoad, "How did we succeed in Init then?");
 
   // Whether we draw the broken or loading icon.
-  bool isLoading = IMAGE_OK(GetContent()->AsElement()->State(), true);
+  bool isLoading = ImageOk(mContent->AsElement()->State());
 
   // Calculate the inner area
   nsRect  inner = GetInnerArea() + aPt;
@@ -1756,8 +1749,7 @@ nsImageFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                               getter_AddRefs(currentRequest));
     }
 
-    EventStates contentState = mContent->AsElement()->State();
-    bool imageOK = IMAGE_OK(contentState, true);
+    bool imageOK = ImageOk(mContent->AsElement()->State());
 
     // XXX(seth): The SizeIsAvailable check here should not be necessary - the
     // intention is that a non-null mImage means we have a size, but there is
diff --git a/layout/style/res/html.css b/layout/style/res/html.css
index 1f572467f..44e41c8d0 100644
--- a/layout/style/res/html.css
+++ b/layout/style/res/html.css
@@ -637,7 +637,6 @@ hr[size="1"] {
 
 img:-moz-broken::before, input:-moz-broken::before,
 img:-moz-user-disabled::before, input:-moz-user-disabled::before,
-img:-moz-loading::before, input:-moz-loading::before,
 applet:-moz-empty-except-children-with-localname(param):-moz-broken::before,
 applet:-moz-empty-except-children-with-localname(param):-moz-user-disabled::before {
   content: -moz-alt-content !important;
-- 
cgit v1.2.3