Move ExpandToParagraphBoundary to VisibleUnits

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

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 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
@@ skipping 2125 matching lines @@
   VisiblePosition pos = p;
   do {
     VisiblePosition n = NextLinePosition(pos, x);
     if (n.IsNull() || n.DeepEquivalent() == pos.DeepEquivalent())
       break;
     pos = n;
   } while (InSameParagraph(p, pos));
   return pos;
 }
 
+EphemeralRange ExpandToParagraphBoundary(const EphemeralRange& range) {
+  const VisiblePosition& start = CreateVisiblePosition(range.StartPosition());
+  DCHECK(start.IsNotNull()) << range.StartPosition();
+  const Position& paragraph_start = StartOfParagraph(start).DeepEquivalent();
+  DCHECK(paragraph_start.IsNotNull()) << range.StartPosition();
+
+  const VisiblePosition& end = CreateVisiblePosition(range.EndPosition());
+  DCHECK(end.IsNotNull()) << range.EndPosition();
+  const Position& paragraph_end = EndOfParagraph(end).DeepEquivalent();
+  DCHECK(paragraph_end.IsNotNull()) << range.EndPosition();
+
+  // TODO(xiaochengh): There are some cases (crbug.com/640112) where we get
+  // |paragraphStart > paragraphEnd|, which is the reason we cannot directly
+  // return |EphemeralRange(paragraphStart, paragraphEnd)|. This is not
+  // desired, though. We should do more investigation to ensure that why
+  // |paragraphStart <= paragraphEnd| is violated.
+  const Position& result_start =
+      paragraph_start.IsNotNull() && paragraph_start <= range.StartPosition()
+          ? paragraph_start
+          : range.StartPosition();
+  const Position& result_end =
+      paragraph_end.IsNotNull() && paragraph_end >= range.EndPosition()
+          ? paragraph_end
+          : range.EndPosition();
+  return EphemeralRange(result_start, result_end);
+}
+
 // ---------
 
 VisiblePosition StartOfBlock(const VisiblePosition& visible_position,
                              EditingBoundaryCrossingRule rule) {
   DCHECK(visible_position.IsValid()) << visible_position;
   Position position = visible_position.DeepEquivalent();
   Element* start_block =
       position.ComputeContainerNode()
           ? EnclosingBlock(position.ComputeContainerNode(), rule)
           : 0;
@@ skipping 1916 matching lines @@
 
 Position SkipWhitespace(const Position& position) {
   return SkipWhitespaceAlgorithm(position);
 }
 
 PositionInFlatTree SkipWhitespace(const PositionInFlatTree& position) {
   return SkipWhitespaceAlgorithm(position);
 }
 
 }  // namespace blink