Revert of Tracking filter mutation via SVGElementProxy

third_party/WebKit/Source/core/layout/svg/ReferenceFilterBuilder.cpp

Index: third_party/WebKit/Source/core/layout/svg/ReferenceFilterBuilder.cpp
diff --git a/third_party/WebKit/Source/core/layout/svg/ReferenceFilterBuilder.cpp b/third_party/WebKit/Source/core/layout/svg/ReferenceFilterBuilder.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..b0a0a0a24ba7cddcf805277b53f3488a2db930b1
--- /dev/null
+++ b/third_party/WebKit/Source/core/layout/svg/ReferenceFilterBuilder.cpp
@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2013 Adobe Systems Inc. All rights reserved.
+ * Copyright (C) 2013 Google Inc.  All rights reserved.
+ * Copyright (C) 2011 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core/layout/svg/ReferenceFilterBuilder.h"
+
+#include "core/dom/Element.h"
+#include "core/fetch/DocumentResource.h"
+#include "core/style/FilterOperation.h"
+#include "core/svg/SVGDocumentExtensions.h"
+#include "core/svg/SVGFilterElement.h"
+
+namespace blink {
+
+namespace {
+
+using ResourceReferenceMap =
+    PersistentHeapHashMap<WeakMember<const FilterOperation>,
+                          Member<DocumentResourceReference>>;
+
+ResourceReferenceMap& documentResourceReferences() {
+  DEFINE_STATIC_LOCAL(ResourceReferenceMap, documentResourceReferences, ());
+  return documentResourceReferences;
+}
+
+}  // namespace
+
+DocumentResourceReference* ReferenceFilterBuilder::documentResourceReference(
+    const FilterOperation* filterOperation) {
+  return documentResourceReferences().get(filterOperation);
+}
+
+void ReferenceFilterBuilder::setDocumentResourceReference(
+    const FilterOperation* filterOperation,
+    DocumentResourceReference* documentResourceReference) {
+  ASSERT(!documentResourceReferences().contains(filterOperation));
+  documentResourceReferences().add(filterOperation, documentResourceReference);
+}
+
+SVGFilterElement* ReferenceFilterBuilder::resolveFilterReference(
+    const ReferenceFilterOperation& filterOperation,
+    Element& element) {
+  TreeScope* treeScope = &element.treeScope();
+
+  if (DocumentResourceReference* documentResourceRef =
+          documentResourceReference(&filterOperation)) {
+    // If we have an SVG document, this is an external reference. Otherwise
+    // we look up the referenced node in the current document.
+    if (DocumentResource* cachedSVGDocument = documentResourceRef->document())
+      treeScope = cachedSVGDocument->document();
+  }
+
+  if (!treeScope)
+    return nullptr;
+
+  Element* filter = treeScope->getElementById(filterOperation.fragment());
+
+  if (!filter) {
+    // Although we did not find the referenced filter, it might exist later
+    // in the document.
+    treeScope->document().accessSVGExtensions().addPendingResource(
+        filterOperation.fragment(), &element);
+    return nullptr;
+  }
+
+  if (!isSVGFilterElement(*filter))
+    return nullptr;
+
+  return toSVGFilterElement(filter);
+}
+
+}  // namespace blink