Fold SVGResourcesCache::ResourceReferenceChanged

Fold SVGResourcesCache::ResourceReferenceChanged into its two users,
greatly tailoring the resulting code for one user (SVGPatternElement).
Expose a function for updating the SVGResources object.

Bug: 1028063
Change-Id: I439ca043c659bad7dbb3fa89d9a4d3d9578f7c17
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2489650Reviewed-by: Stephen Chenney <schenney@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#820179}

third_party/blink/renderer/core/layout/svg/svg_resources.cc

@@ -725,14 +725,19 @@ void SVGElementResourceClient::ResourceContentChanged(
 }
 
 void SVGElementResourceClient::ResourceElementChanged() {
-  if (LayoutObject* layout_object = element_->GetLayoutObject()) {
-    ClearFilterData();
-    SVGResourcesCache::ResourceReferenceChanged(*layout_object);
-    // TODO(fs): If the resource element (for a filter) doesn't actually change
-    // we don't need to perform the associated invalidations.
-    layout_object->SetNeedsPaintPropertyUpdate();
-    MarkFilterDataDirty();
+  LayoutObject* layout_object = element_->GetLayoutObject();
+  if (!layout_object)
+    return;
+  ClearFilterData();
+  if (layout_object->Parent()) {
+    SVGResourcesCache::UpdateResources(*layout_object);
+    LayoutSVGResourceContainer::MarkForLayoutAndParentResourceInvalidation(
+        *layout_object, true);
   }
+  // TODO(fs): If the resource element (for a filter) doesn't actually change
+  // we don't need to perform the associated invalidations.
+  layout_object->SetNeedsPaintPropertyUpdate();
+  MarkFilterDataDirty();
 }
 
 void SVGElementResourceClient::ResourceDestroyed(

third_party/blink/renderer/core/layout/svg/svg_resources_cache.cc

@@ -109,19 +109,11 @@ void SVGResourcesCache::ClientStyleChanged(LayoutObject& layout_object,
 
   // LayoutObjects for SVGFE*Element should not be calling this function.
   DCHECK(!layout_object.IsSVGFilterPrimitive());
-  // We only call this function on LayoutObjects that fulfil this condition.
-  DCHECK(LayoutObjectCanHaveResources(layout_object));
 
   // Dynamic changes of CSS properties like 'clip-path' may require us to
   // recompute the associated resources for a LayoutObject.
-  // TODO(fs): Avoid passing in a useless StyleDifference, but instead compare
-  // oldStyle/newStyle to see which resources changed to be able to selectively
-  // rebuild individual resources, instead of all of them.
-  SVGResourcesCache& cache = ResourcesCache(layout_object.GetDocument());
-  if (cache.UpdateResourcesFromLayoutObject(layout_object,
-                                            layout_object.StyleRef())) {
+  if (UpdateResources(layout_object))
     layout_object.SetNeedsPaintPropertyUpdate();
-  }
 
   // If this layoutObject is the child of ResourceContainer and it require
   // repainting that changes of CSS properties such as 'visibility',
@@ -133,28 +125,6 @@ void SVGResourcesCache::ClientStyleChanged(LayoutObject& layout_object,
       layout_object, needs_layout);
 }
 
-void SVGResourcesCache::ResourceReferenceChanged(LayoutObject& layout_object) {
-  DCHECK(layout_object.IsSVG());
-  DCHECK(layout_object.GetNode());
-  DCHECK(layout_object.GetNode()->IsSVGElement());
-
-  if (!layout_object.Parent())
-    return;
-
-  // Only LayoutObjects that can actually have resources should be pending and
-  // hence be able to call this method.
-  DCHECK(LayoutObjectCanHaveResources(layout_object));
-
-  SVGResourcesCache& cache = ResourcesCache(layout_object.GetDocument());
-  if (cache.UpdateResourcesFromLayoutObject(layout_object,
-                                            layout_object.StyleRef())) {
-    layout_object.SetNeedsPaintPropertyUpdate();
-  }
-
-  LayoutSVGResourceContainer::MarkForLayoutAndParentResourceInvalidation(
-      layout_object, true);
-}
-
 void SVGResourcesCache::ClientWasAddedToTree(LayoutObject& layout_object) {
   DCHECK(LayoutObjectCanHaveResources(layout_object));
   LayoutSVGResourceContainer::MarkForLayoutAndParentResourceInvalidation(
@@ -177,6 +147,13 @@ void SVGResourcesCache::ClientWillBeRemovedFromTree(
     layout_object.SetNeedsPaintPropertyUpdate();
 }
 
+bool SVGResourcesCache::UpdateResources(LayoutObject& layout_object) {
+  DCHECK(LayoutObjectCanHaveResources(layout_object));
+  SVGResourcesCache& cache = ResourcesCache(layout_object.GetDocument());
+  return cache.UpdateResourcesFromLayoutObject(layout_object,
+                                               layout_object.StyleRef());
+}
+
 void SVGResourcesCache::ClientDestroyed(LayoutObject& layout_object) {
   SVGResourcesCache& cache = ResourcesCache(layout_object.GetDocument());
   cache.RemoveResourcesFromLayoutObject(layout_object);

third_party/blink/renderer/core/layout/svg/svg_resources_cache.h

@@ -56,8 +56,9 @@ class SVGResourcesCache {
   static void ClientStyleChanged(LayoutObject&, StyleDifference);
 
   // Called when the target element of a resource referenced by the
-  // LayoutObject may have changed.
-  static void ResourceReferenceChanged(LayoutObject&);
+  // LayoutObject may have changed and we need to recreate the
+  // associated SVGResources object.
+  static bool UpdateResources(LayoutObject&);
 
   class TemporaryStyleScope {
     STACK_ALLOCATED();

third_party/blink/renderer/core/svg/svg_pattern_element.cc

@@ -115,8 +115,12 @@ void SVGPatternElement::BuildPendingResource() {
     resource_->AddClient(EnsureSVGResourceClient());
 
   InvalidatePattern(layout_invalidation_reason::kSvgResourceInvalidated);
-  if (auto* layout_object = GetLayoutObject())
-    SVGResourcesCache::ResourceReferenceChanged(*layout_object);
+  if (auto* layout_object = GetLayoutObject()) {
+    if (!layout_object->Parent())
+      return;
+    SVGResourcesCache::UpdateResources(*layout_object);
+    InvalidateDependentPatterns();
+  }
 }
 
 void SVGPatternElement::ClearResourceReferences() {
@@ -200,6 +204,15 @@ void SVGPatternElement::InvalidatePattern(
     layout_object->InvalidateCacheAndMarkForLayout(reason);
 }
 
+void SVGPatternElement::InvalidateDependentPatterns() {
+  NotifyIncomingReferences([](SVGElement& element) {
+    if (auto* pattern = DynamicTo<SVGPatternElement>(element)) {
+      pattern->InvalidatePattern(
+          layout_invalidation_reason::kSvgResourceInvalidated);
+    }
+  });
+}
+
 LayoutObject* SVGPatternElement::CreateLayoutObject(const ComputedStyle&,
                                                     LegacyLayout) {
   return new LayoutSVGResourcePattern(this);

third_party/blink/renderer/core/svg/svg_pattern_element.h

@@ -76,6 +76,7 @@ class SVGPatternElement final : public SVGElement,
   }
 
   void InvalidatePattern(LayoutInvalidationReasonForTracing);
+  void InvalidateDependentPatterns();
 
   const SVGPatternElement* ReferencedElement() const;