Reduce calls to LoadPendingImages.

There is no need for the extra call after ApplyAnimatedStandardProperties
now that we trigger loading at the end of StyleForElement and
PseudoStyleForElement. Also, we only need to have the extra loading for
MatchedPropertiesCache case if when we actually add the ComputedStyle to
the cache.

Change-Id: I943c24f42f8ec945b901cdbf7572361dc68e280b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2216076Reviewed-by: Anders Hartvoll Ruud <andruud@chromium.org>
Commit-Queue: Rune Lillesveen <futhark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#772159}

third_party/blink/renderer/core/css/resolver/style_resolver.cc

@@ -1464,9 +1464,6 @@ bool StyleResolver::ApplyAnimatedStandardProperties(
                                                           standard_transitions);
   }
 
-  // Start loading resources used by animations.
-  state.LoadPendingResources();
-
   DCHECK(!state.GetFontBuilder().FontDirty());
 
   return true;
@@ -1900,6 +1897,7 @@ void StyleResolver::MaybeAddToMatchedPropertiesCache(
       MatchedPropertiesCache::IsCacheable(state)) {
     INCREMENT_STYLE_STATS_COUNTER(GetDocument().GetStyleEngine(),
                                   matched_property_cache_added, 1);
+    state.LoadPendingResources();
     matched_properties_cache_.Add(cache_success.key, *state.Style(),
                                   *state.ParentStyle(), state.Dependencies());
   }
@@ -2077,7 +2075,6 @@ void StyleResolver::ApplyMatchedLowPriorityProperties(
         state, match_result, apply_inherited_only, needs_apply_pass);
   }
 
-  state.LoadPendingResources();
   MaybeAddToMatchedPropertiesCache(state, cache_success, match_result);
 
   DCHECK(!state.GetFontBuilder().FontDirty());
@@ -2177,7 +2174,6 @@ void StyleResolver::CascadeAndApplyMatchedProperties(StyleResolverState& state,
     cascade.Apply();
   }
 
-  state.LoadPendingResources();
   MaybeAddToMatchedPropertiesCache(state, cache_success, result);
 
   DCHECK(!state.GetFontBuilder().FontDirty());