TEXTAREA: Cutting last line without EOL should not remove the remaining EOL in the previous line.

third_party/WebKit/Source/core/editing/commands/InsertLineBreakCommand.cpp

 /*
  * Copyright (C) 2005, 2006 Apple Computer, 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
@@ skipping 18 matching lines @@
 #include "core/dom/Document.h"
 #include "core/dom/Text.h"
 #include "core/editing/EditingStyle.h"
 #include "core/editing/EditingUtilities.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/VisiblePosition.h"
 #include "core/editing/VisibleUnits.h"
 #include "core/frame/LocalFrame.h"
 #include "core/html/HTMLBRElement.h"
 #include "core/html/HTMLElement.h"
+#include "core/html/HTMLTextFormControlElement.h"
 #include "core/layout/LayoutObject.h"
 #include "core/layout/LayoutText.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 InsertLineBreakCommand::InsertLineBreakCommand(Document& document)
     : CompositeEditCommand(document)
 {
 }
 
 bool InsertLineBreakCommand::preservesTypingStyle() const
 {
     return true;
 }
 
 // Whether we should insert a break element or a '\n'.
 bool InsertLineBreakCommand::shouldUseBreakElement(const Position& insertionPos)
 {
     // An editing position like [input, 0] actually refers to the position before
     // the input element, and in that case we need to check the input element's
     // parent's layoutObject.
     Position p(insertionPos.parentAnchoredEquivalent());
-    return p.anchorNode()->layoutObject() && !p.anchorNode()->layoutObject()->style()->preserveNewline();
+    return isRichlyEditablePosition(p) && p.anchorNode()->layoutObject() && !p.anchorNode()->layoutObject()->style()->preserveNewline();
 }
 
 void InsertLineBreakCommand::doApply(EditingState* editingState)
 {
     deleteSelection(editingState);
     if (editingState->isAborted())
         return;
     VisibleSelection selection = endingSelection();
     if (!selection.isNonOrphanedCaretOrRange())
         return;
@@ skipping 21 matching lines @@
     // FIXME: Need to merge text nodes when inserting just after or before text.
 
     if (isEndOfParagraph(caret) && !lineBreakExistsAtVisiblePosition(caret)) {
         bool needExtraLineBreak = !isHTMLHRElement(*pos.anchorNode()) && !isHTMLTableElement(*pos.anchorNode());
 
         insertNodeAt(nodeToInsert.get(), pos, editingState);
         if (editingState->isAborted())
             return;
 
         if (needExtraLineBreak) {
-            insertNodeBefore(nodeToInsert->cloneNode(false), nodeToInsert, editingState);
+            RefPtrWillBeRawPtr<Node> extraNode;
+            // TODO(tkent): Can we remove HTMLTextFormControlElement dependency?
+            if (HTMLTextFormControlElement* textControl = enclosingTextFormControl(nodeToInsert.get()))
+                extraNode = textControl->createPlaceholderBreakElement();
+            else
+                extraNode = nodeToInsert->cloneNode(false);
+            insertNodeAfter(extraNode.get(), nodeToInsert, editingState);
             if (editingState->isAborted())
                 return;
+            nodeToInsert = extraNode.release();
         }
 
         VisiblePosition endingPosition = createVisiblePosition(positionBeforeNode(nodeToInsert.get()));
         setEndingSelection(VisibleSelection(endingPosition, endingSelection().isDirectional()));
     } else if (pos.computeEditingOffset() <= caretMinOffset(pos.anchorNode())) {
         insertNodeAt(nodeToInsert.get(), pos, editingState);
         if (editingState->isAborted())
             return;
 
         // Insert an extra br or '\n' if the just inserted one collapsed.
@@ skipping 62 matching lines @@
         // before the line break (if the line break is at the end of a block it isn't selectable).
         // So, this next call sets the endingSelection() to a caret just after the line break
         // that we inserted, or just before it if it's at the end of a block.
         setEndingSelection(endingSelection().visibleEnd());
     }
 
     rebalanceWhitespace();
 }
 
 } // namespace blink