Reland of "Tracking reference filter mutation via SVGElementProxy"

third_party/WebKit/Source/core/style/FilterOperations.cpp

Index: third_party/WebKit/Source/core/style/FilterOperations.cpp
diff --git a/third_party/WebKit/Source/core/style/FilterOperations.cpp b/third_party/WebKit/Source/core/style/FilterOperations.cpp
index 66e8fea6edfe19ebd91710a0cd93fadc7ca7dccb..06d944ce4532a426d7e96301dcc1aafda8cbf40b 100644
--- a/third_party/WebKit/Source/core/style/FilterOperations.cpp
+++ b/third_party/WebKit/Source/core/style/FilterOperations.cpp
@@ -25,9 +25,6 @@
 
 #include "core/style/FilterOperations.h"
 
-#include "platform/LengthFunctions.h"
-#include "platform/geometry/IntSize.h"
-#include "platform/graphics/filters/FEGaussianBlur.h"
 #include <numeric>
 
 namespace blink {
@@ -108,4 +105,18 @@ bool FilterOperations::hasFilterThatMovesPixels() const {
   return false;
 }
 
+void FilterOperations::addClient(SVGResourceClient* client) const {
+  for (FilterOperation* operation : m_operations) {
+    if (operation->type() == FilterOperation::REFERENCE)
+      toReferenceFilterOperation(*operation).addClient(client);
+  }
+}
+
+void FilterOperations::removeClient(SVGResourceClient* client) const {
+  for (FilterOperation* operation : m_operations) {
+    if (operation->type() == FilterOperation::REFERENCE)
+      toReferenceFilterOperation(*operation).removeClient(client);
+  }
+}
+
 }  // namespace blink