Rewrite DocumentMarkerController to use SynchronousMutationObserver

third_party/WebKit/Source/core/dom/Document.cpp

Index: third_party/WebKit/Source/core/dom/Document.cpp
diff --git a/third_party/WebKit/Source/core/dom/Document.cpp b/third_party/WebKit/Source/core/dom/Document.cpp
index 39cc41ea019a37bff37e21b26bed993b5b627160..a4444faefae0201988277f9dba205a73fa06fb3a 100644
--- a/third_party/WebKit/Source/core/dom/Document.cpp
+++ b/third_party/WebKit/Source/core/dom/Document.cpp
@@ -4324,16 +4324,11 @@ void Document::nodeWillBeRemoved(Node& n) {
 void Document::didInsertText(Node* text, unsigned offset, unsigned length) {
   for (Range* range : m_ranges)
     range->didInsertText(text, offset, length);
-
-  m_markers->shiftMarkers(text, offset, length);
 }
 
 void Document::didRemoveText(Node* text, unsigned offset, unsigned length) {
   for (Range* range : m_ranges)
     range->didRemoveText(text, offset, length);
-
-  m_markers->removeMarkers(text, offset, length);
-  m_markers->shiftMarkers(text, offset + length, 0 - length);
 }
 
 void Document::didMergeTextNodes(const Text& mergedNode,