Proactively dispose image filters for SVG filter chains

third_party/WebKit/Source/platform/graphics/filters/FilterEffect.cpp

Index: third_party/WebKit/Source/platform/graphics/filters/FilterEffect.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/filters/FilterEffect.cpp b/third_party/WebKit/Source/platform/graphics/filters/FilterEffect.cpp
index 36ef9c7b47b5830f33bdc605082515b065687a0c..8dcb7eef2fd38c19a9fa6b358316c81898a56072 100644
--- a/third_party/WebKit/Source/platform/graphics/filters/FilterEffect.cpp
+++ b/third_party/WebKit/Source/platform/graphics/filters/FilterEffect.cpp
@@ -88,11 +88,19 @@ FilterEffect* FilterEffect::InputEffect(unsigned number) const {
   return input_effects_.at(number).Get();
 }
 
-void FilterEffect::ClearResult() {
+void FilterEffect::DisposeImageFilters() {
   for (int i = 0; i < 4; i++)
     image_filters_[i] = nullptr;
 }
 
+void FilterEffect::DisposeImageFiltersRecursive() {
+  if (!HasImageFilter())
+    return;
+  DisposeImageFilters();
+  for (auto& effect : input_effects_)
+    effect->DisposeImageFiltersRecursive();
+}
+
 Color FilterEffect::AdaptColorToOperatingColorSpace(const Color& device_color) {
   // |deviceColor| is assumed to be DeviceRGB.
   return ColorSpaceUtilities::ConvertColor(device_color, OperatingColorSpace());