Worklet: Lazily create PaintWorkletGlobalScopes

third_party/WebKit/Source/modules/csspaint/PaintWorkletGlobalScope.cpp

Index: third_party/WebKit/Source/modules/csspaint/PaintWorkletGlobalScope.cpp
diff --git a/third_party/WebKit/Source/modules/csspaint/PaintWorkletGlobalScope.cpp b/third_party/WebKit/Source/modules/csspaint/PaintWorkletGlobalScope.cpp
index 20c8688b9b8949bd3a2610b857ddb814d70c7b69..64318718a9bdbd9aafbd056c9828f4704ac82d35 100644
--- a/third_party/WebKit/Source/modules/csspaint/PaintWorkletGlobalScope.cpp
+++ b/third_party/WebKit/Source/modules/csspaint/PaintWorkletGlobalScope.cpp
@@ -45,7 +45,8 @@ PaintWorkletGlobalScope::PaintWorkletGlobalScope(
                                    url,
                                    user_agent,
                                    std::move(security_origin),
-                                   isolate) {}
+                                   isolate),
+      pending_generator_registry_(new PaintWorkletPendingGeneratorRegistry) {}
 
 PaintWorkletGlobalScope::~PaintWorkletGlobalScope() {}
 
@@ -193,17 +194,7 @@ void PaintWorkletGlobalScope::registerPaint(const String& name,
       native_invalidation_properties, custom_invalidation_properties,
       input_argument_types, has_alpha);
   paint_definitions_.Set(name, definition);
-
-  // Set the definition on any pending generators.
-  GeneratorHashSet* set = pending_generators_.at(name);
-  if (set) {
-    for (const auto& generator : *set) {
-      if (generator) {
-        generator->SetDefinition(definition);
-      }
-    }
-  }
-  pending_generators_.erase(name);
+  pending_generator_registry_->SetDefinition(name, definition);
 }
 
 CSSPaintDefinition* PaintWorkletGlobalScope::FindDefinition(
@@ -214,16 +205,12 @@ CSSPaintDefinition* PaintWorkletGlobalScope::FindDefinition(
 void PaintWorkletGlobalScope::AddPendingGenerator(
     const String& name,
     CSSPaintImageGeneratorImpl* generator) {
-  Member<GeneratorHashSet>& set =
-      pending_generators_.insert(name, nullptr).stored_value->value;
-  if (!set)
-    set = new GeneratorHashSet;
-  set->insert(generator);
+  pending_generator_registry_->AddPendingGenerator(name, generator);
 }
 
 DEFINE_TRACE(PaintWorkletGlobalScope) {
   visitor->Trace(paint_definitions_);
-  visitor->Trace(pending_generators_);
+  visitor->Trace(pending_generator_registry_);
   MainThreadWorkletGlobalScope::Trace(visitor);
 }