1 files changed, 52 insertions, 0 deletions
diff --git a/chromium/third_party/blink/renderer/platform/graphics/memory_managed_paint_canvas.h b/chromium/third_party/blink/renderer/platform/graphics/memory_managed_paint_canvas.h
new file mode 100644
index 00000000000..444d771f899
--- /dev/null
+++ b/chromium/third_party/blink/renderer/platform/graphics/memory_managed_paint_canvas.h
@@ -0,0 +1,52 @@
+// Copyright 2019 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 THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_MEMORY_MANAGED_PAINT_CANVAS_H_
+#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_MEMORY_MANAGED_PAINT_CANVAS_H_
+
+#include <memory>
+
+#include "cc/paint/record_paint_canvas.h"
+#include "third_party/blink/public/platform/platform.h"
+
+namespace blink {
+
+// MemoryManagedPaintCanvas overrides the potentially memory intensive image
+// drawing methods of PaintCanvas and keeps track of how much memory is
+// being pinned between flushes. This allows the rendering context to flush if
+// too much memory is used.
+class PLATFORM_EXPORT MemoryManagedPaintCanvas final
+    : public cc::RecordPaintCanvas {
+ public:
+  MemoryManagedPaintCanvas(cc::DisplayItemList* list,
+                           const SkRect& bounds,
+                           base::RepeatingClosure set_needs_flush_callback);
+  explicit MemoryManagedPaintCanvas(const cc::RecordPaintCanvas&) = delete;
+  ~MemoryManagedPaintCanvas() override;
+
+  void drawImage(const cc::PaintImage& image,
+                 SkScalar left,
+                 SkScalar top,
+                 const cc::PaintFlags* flags) override;
+  void drawImageRect(const cc::PaintImage& image,
+                     const SkRect& src,
+                     const SkRect& dst,
+                     const cc::PaintFlags* flags,
+                     SrcRectConstraint constraint) override;
+
+ private:
+  void UpdateMemoryUsage(const cc::PaintImage& image);
+
+  base::flat_set<int> cached_image_ids_;
+  uint64_t total_stored_image_memory_ = 0;
+
+  base::RepeatingClosure set_needs_flush_callback_;
+
+  // The same value as is used in content::WebGraphicsConext3DProviderImpl.
+  static constexpr uint64_t kMaxPinnedMemory = 64 * 1024 * 1024;
+};
+
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_MEMORY_MANAGED_PAINT_CANVAS_H_