Worklet: Lazily create PaintWorkletGlobalScopes

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

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PaintWorkletGlobalScope_h
 #define PaintWorkletGlobalScope_h
 
 #include "bindings/core/v8/ScriptValue.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/workers/MainThreadWorkletGlobalScope.h"
 #include "modules/ModulesExport.h"
+#include "modules/csspaint/PaintWorkletPendingGeneratorRegistry.h"
 #include "platform/graphics/ImageBuffer.h"
 
 namespace blink {
 
 class CSSPaintDefinition;
-class CSSPaintImageGeneratorImpl;
 class ExceptionState;
 
 class MODULES_EXPORT PaintWorkletGlobalScope final
     : public MainThreadWorkletGlobalScope {
   DEFINE_WRAPPERTYPEINFO();
   USING_GARBAGE_COLLECTED_MIXIN(PaintWorkletGlobalScope);
 
  public:
   static PaintWorkletGlobalScope* Create(LocalFrame*,
                                          const KURL&,
                                          const String& user_agent,
                                          PassRefPtr<SecurityOrigin>,
-                                         v8::Isolate*);
+                                         v8::Isolate*,
+                                         PaintWorkletPendingGeneratorRegistry*);
   ~PaintWorkletGlobalScope() override;
   void Dispose() final;
 
   bool IsPaintWorkletGlobalScope() const final { return true; }
   void registerPaint(const String& name,
                      const ScriptValue& ctor,
                      ExceptionState&);
 
   CSSPaintDefinition* FindDefinition(const String& name);
-  void AddPendingGenerator(const String& name, CSSPaintImageGeneratorImpl*);
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   PaintWorkletGlobalScope(LocalFrame*,
                           const KURL&,
                           const String& user_agent,
                           PassRefPtr<SecurityOrigin>,
-                          v8::Isolate*);
+                          v8::Isolate*,
+                          PaintWorkletPendingGeneratorRegistry*);
 
+  // The implementation of the "paint definition" concept:
+  // https://drafts.css-houdini.org/css-paint-api/#paint-definition
   typedef HeapHashMap<String, Member<CSSPaintDefinition>> DefinitionMap;
   DefinitionMap paint_definitions_;
 
-  // The map of CSSPaintImageGeneratorImpl which are waiting for a
-  // CSSPaintDefinition to be registered. The global scope is expected to
-  // outlive the generators hence are held onto with a WeakMember.
-  typedef HeapHashSet<WeakMember<CSSPaintImageGeneratorImpl>> GeneratorHashSet;
-  typedef HeapHashMap<String, Member<GeneratorHashSet>> PendingGeneratorMap;
-  PendingGeneratorMap pending_generators_;
+  Member<PaintWorkletPendingGeneratorRegistry> pending_generator_registry_;
 };
 
 DEFINE_TYPE_CASTS(PaintWorkletGlobalScope,
                   ExecutionContext,
                   context,
                   context->IsPaintWorkletGlobalScope(),
                   context.IsPaintWorkletGlobalScope());
 
 }  // namespace blink
 
 #endif  // PaintWorkletGlobalScope_h