Add TextMatchMarkerList in preparation for DocumentMarkerController refactor

third_party/WebKit/Source/core/editing/markers/DocumentMarkerController.cpp

Index: third_party/WebKit/Source/core/editing/markers/DocumentMarkerController.cpp
diff --git a/third_party/WebKit/Source/core/editing/markers/DocumentMarkerController.cpp b/third_party/WebKit/Source/core/editing/markers/DocumentMarkerController.cpp
index 32abf9d8d5a5e3cbf05e521a1eefd3c3a0ca172d..5fc02e1cd1af11e3a209c22ea2d18f85a7c369b5 100644
--- a/third_party/WebKit/Source/core/editing/markers/DocumentMarkerController.cpp
+++ b/third_party/WebKit/Source/core/editing/markers/DocumentMarkerController.cpp
@@ -373,7 +373,7 @@ void DocumentMarkerController::removeMarkers(
     MarkerList::iterator startPos =
         std::upper_bound(list->begin(), list->end(), startOffset, endsBefore);
     for (MarkerList::iterator i = startPos; i != list->end();) {
-      DocumentMarker marker(*i->get());
+      const DocumentMarker& marker(*i->get());
 
       // markers are returned in order, so stop if we are now past the specified
       // range
@@ -393,18 +393,18 @@ void DocumentMarkerController::removeMarkers(
 
       // add either of the resulting slices that are left after removing target
       if (startOffset > marker.startOffset()) {
-        DocumentMarker newLeft = marker;
-        newLeft.setEndOffset(startOffset);
+        DocumentMarker* newLeft = marker.clone();
+        newLeft->setEndOffset(startOffset);
         size_t insertIndex = i - list->begin();
-        list->insert(insertIndex, RenderedDocumentMarker::create(newLeft));
+        list->insert(insertIndex, RenderedDocumentMarker::create(*newLeft));
         // Move to the marker after the inserted one.
         i = list->begin() + insertIndex + 1;
       }
       if (marker.endOffset() > endOffset) {
-        DocumentMarker newRight = marker;
-        newRight.setStartOffset(endOffset);
+        DocumentMarker* newRight = marker.clone();
+        newRight->setStartOffset(endOffset);
         size_t insertIndex = i - list->begin();
-        list->insert(insertIndex, RenderedDocumentMarker::create(newRight));
+        list->insert(insertIndex, RenderedDocumentMarker::create(*newRight));
         // Move to the marker after the inserted one.
         i = list->begin() + insertIndex + 1;
       }