Do another merge using nifty new merge script (CL for that coming soon).

third_party/WebKit/WebCore/editing/DeleteSelectionCommand.cpp

 /*
  * Copyright (C) 2005 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 61 matching lines @@
     return true;
 }
 
 DeleteSelectionCommand::DeleteSelectionCommand(Document *document, bool smartDelete, bool mergeBlocksAfterDelete, bool replace, bool expandForSpecialElements)
     : CompositeEditCommand(document), 
       m_hasSelectionToDelete(false), 
       m_smartDelete(smartDelete), 
       m_mergeBlocksAfterDelete(mergeBlocksAfterDelete),
       m_replace(replace),
       m_expandForSpecialElements(expandForSpecialElements),
+      m_pruneStartBlockIfNecessary(false),
       m_startBlock(0),
       m_endBlock(0),
       m_typingStyle(0),
       m_deleteIntoBlockquoteStyle(0)
 {
 }
 
 DeleteSelectionCommand::DeleteSelectionCommand(const Selection& selection, bool smartDelete, bool mergeBlocksAfterDelete, bool replace, bool expandForSpecialElements)
     : CompositeEditCommand(selection.start().node()->document()), 
       m_hasSelectionToDelete(true), 
       m_smartDelete(smartDelete), 
       m_mergeBlocksAfterDelete(mergeBlocksAfterDelete),
       m_replace(replace),
       m_expandForSpecialElements(expandForSpecialElements),
+      m_pruneStartBlockIfNecessary(false),
       m_selectionToDelete(selection),
       m_startBlock(0),
       m_endBlock(0),
       m_typingStyle(0),
       m_deleteIntoBlockquoteStyle(0)
 {
 }
 
 void DeleteSelectionCommand::initializeStartEnd(Position& start, Position& end)
 {
@@ skipping 76 matching lines @@
         m_mergeBlocksAfterDelete = false;
     
     // Usually the start and the end of the selection to delete are pulled together as a result of the deletion.
     // Sometimes they aren't (like when no merge is requested), so we must choose one position to hold the caret 
     // and receive the placeholder after deletion.
     VisiblePosition visibleEnd(m_downstreamEnd);
     if (m_mergeBlocksAfterDelete && !isEndOfParagraph(visibleEnd))
         m_endingPosition = m_downstreamEnd;
     else
         m_endingPosition = m_downstreamStart;
+    
+    // We don't want to merge into a block if it will mean changing the quote level of content after deleting 
+    // selections that contain a whole number paragraphs plus a line break, since it is unclear to most users 
+    // that such a selection actually ends at the start of the next paragraph. This matches TextEdit behavior 
+    // for indented paragraphs.
+    if (numEnclosingMailBlockquotes(start) != numEnclosingMailBlockquotes(end) && isStartOfParagraph(visibleEnd) && isStartOfParagraph(VisiblePosition(start))) {
+        m_mergeBlocksAfterDelete = false;
+        m_pruneStartBlockIfNecessary = true;
+    }
 
     // Handle leading and trailing whitespace, as well as smart delete adjustments to the selection
     m_leadingWhitespace = m_upstreamStart.leadingWhitespacePosition(m_selectionToDelete.affinity());
     m_trailingWhitespace = m_downstreamEnd.trailingWhitespacePosition(VP_DEFAULT_AFFINITY);
 
     if (m_smartDelete) {
     
         // skip smart delete if the selection to delete already starts or ends with whitespace
         Position pos = VisiblePosition(m_upstreamStart, m_selectionToDelete.affinity()).deepEquivalent();
         bool skipSmartDelete = pos.trailingWhitespacePosition(VP_DEFAULT_AFFINITY, true).isNotNull();
@@ skipping 301 matching lines @@
         Text* textNode = static_cast<Text*>(m_trailingWhitespace.node());
         ASSERT(!textNode->renderer() ||textNode->renderer()->style()->collapseWhiteSpace());
         replaceTextInNode(textNode, m_trailingWhitespace.offset(), 1, nonBreakingSpaceString());
     }
 }
 
 // If a selection starts in one block and ends in another, we have to merge to bring content before the
 // start together with content after the end.
 void DeleteSelectionCommand::mergeParagraphs()
 {
-    if (!m_mergeBlocksAfterDelete)
+    if (!m_mergeBlocksAfterDelete) {
+        if (m_pruneStartBlockIfNecessary) {
+            // Make sure that the ending position isn't inside the block we're about to prune.
+            m_endingPosition = m_downstreamEnd;
+            // We aren't going to merge into the start block, so remove it if it's empty.
+            prune(m_upstreamStart.node());
+            // Removing the start block during a deletion is usually an indication that we need
+            // a placeholder, but not in this case.
+            m_needPlaceholder = false;
+        }
         return;
+    }
+    
+    // It shouldn't have been asked to both try and merge content into the start block and prune it.
+    ASSERT(!m_pruneStartBlockIfNecessary);
 
     // FIXME: Deletion should adjust selection endpoints as it removes nodes so that we never get into this state (4099839).
     if (!m_downstreamEnd.node()->inDocument() || !m_upstreamStart.node()->inDocument())
          return;
          
     // FIXME: The deletion algorithm shouldn't let this happen.
     if (Range::compareBoundaryPoints(m_upstreamStart, m_downstreamEnd) > 0)
         return;
         
     // FIXME: Merging will always be unnecessary in this case, but we really bail here because this is a case where
@@ skipping 256 matching lines @@
 
 // Normally deletion doesn't preserve the typing style that was present before it.  For example,
 // type a character, Bold, then delete the character and start typing.  The Bold typing style shouldn't
 // stick around.  Deletion should preserve a typing style that *it* sets, however.
 bool DeleteSelectionCommand::preservesTypingStyle() const
 {
     return m_typingStyle;
 }
 
 } // namespace WebCore