Revert of Utilize FrameSelection::setSelection() taking SelectionInDOMTree/SelectionInFlatTree

third_party/WebKit/Source/core/editing/DOMSelection.cpp

Index: third_party/WebKit/Source/core/editing/DOMSelection.cpp
diff --git a/third_party/WebKit/Source/core/editing/DOMSelection.cpp b/third_party/WebKit/Source/core/editing/DOMSelection.cpp
index c28eff62c570923843f83084db8d82d4a0f5ebc7..0a1501f0ffea6ca18800ee7703434d1d08b6bad4 100644
--- a/third_party/WebKit/Source/core/editing/DOMSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/DOMSelection.cpp
@@ -222,9 +222,16 @@
     return;
   }
 
+  // TODO(xiaochengh): The use of updateStyleAndLayoutIgnorePendingStylesheets
+  // needs to be audited.  See http://crbug.com/590369 for more details.
+  // In the long term, we should change FrameSelection::setSelection to take a
+  // parameter that does not require clean layout, so that modifying selection
+  // no longer performs synchronous layout by itself.
+  frame()->document()->updateStyleAndLayoutIgnorePendingStylesheets();
+
   SelectionInDOMTree::Builder builder;
   builder.collapse(selection.end());
-  frame()->selection().setSelection(builder.build());
+  frame()->selection().setSelection(createVisibleSelection(builder.build()));
 }
 
 void DOMSelection::collapseToStart(ExceptionState& exceptionState) {
@@ -239,9 +246,16 @@
     return;
   }
 
+  // TODO(xiaochengh): The use of updateStyleAndLayoutIgnorePendingStylesheets
+  // needs to be audited.  See http://crbug.com/590369 for more details.
+  // In the long term, we should change FrameSelection::setSelection to take a
+  // parameter that does not require clean layout, so that modifying selection
+  // no longer performs synchronous layout by itself.
+  frame()->document()->updateStyleAndLayoutIgnorePendingStylesheets();
+
   SelectionInDOMTree::Builder builder;
   builder.collapse(selection.start());
-  frame()->selection().setSelection(builder.build());
+  frame()->selection().setSelection(createVisibleSelection(builder.build()));
 }
 
 void DOMSelection::empty() {