[Reland] Remove style spans to follow the styles of the block element

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

 /*
  * Copyright (C) 2005, 2006, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009, 2010, 2011 Google 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 17 matching lines @@
 
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
 #include "core/CSSPropertyNames.h"
 #include "core/HTMLNames.h"
 #include "core/InputTypeNames.h"
 #include "core/css/CSSStyleDeclaration.h"
 #include "core/css/StylePropertySet.h"
 #include "core/dom/Document.h"
 #include "core/dom/DocumentFragment.h"
 #include "core/dom/Element.h"
+#include "core/dom/NodeComputedStyle.h"
 #include "core/dom/Text.h"
 #include "core/editing/EditingUtilities.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/VisibleUnits.h"
 #include "core/editing/commands/ApplyStyleCommand.h"
 #include "core/editing/commands/BreakBlockquoteCommand.h"
 #include "core/editing/commands/SimplifyMarkupCommand.h"
 #include "core/editing/commands/SmartReplace.h"
 #include "core/editing/iterators/TextIterator.h"
 #include "core/editing/serializers/HTMLInterchange.h"
@@ skipping 739 matching lines @@
             || isHTMLStyleElement(*node)
             || isHTMLTitleElement(*node)) {
             next = NodeTraversal::nextSkippingChildren(*node);
             fragment.removeNode(node);
         } else {
             next = NodeTraversal::next(*node);
         }
     }
 }
 
+static bool followBlockElementStyle(const Node* node)
+{
+    if (!node->isHTMLElement())
+        return false;
+
+    const HTMLElement& element = toHTMLElement(*node);
+    return element.computedStyle()->display() == LIST_ITEM
+        || element.computedStyle()->display() == TABLE_CELL
+        || element.hasTagName(preTag)
+        || element.hasTagName(h1Tag)
+        || element.hasTagName(h2Tag)
+        || element.hasTagName(h3Tag)
+        || element.hasTagName(h4Tag)
+        || element.hasTagName(h5Tag)
+        || element.hasTagName(h6Tag);
+}
+
 // Remove style spans before insertion if they are unnecessary.  It's faster because we'll
 // avoid doing a layout.
 static bool handleStyleSpansBeforeInsertion(ReplacementFragment& fragment, const Position& insertionPos)
 {
     Node* topNode = fragment.firstChild();
     if (!isHTMLSpanElement(topNode))
         return false;
 
     // Handling the case where we are doing Paste as Quotation or pasting into quoted content is more complicated (see handleStyleSpans)
     // and doesn't receive the optimization.
     if (isMailPasteAsQuotationHTMLBlockQuoteElement(topNode) || enclosingNodeOfType(firstPositionInOrBeforeNode(topNode), isMailHTMLBlockquoteElement, CanCrossEditingBoundary))
         return false;
 
-    // Remove style spans to follow the styles of list item when |fragment| becomes a list item.
-    // See bug http://crbug.com/335955.
+    // Remove style spans to follow the styles of parent block element when |fragment| becomes a part of it.
+    // See bugs http://crbug.com/226941 and http://crbug.com/335955.
     HTMLSpanElement* wrappingStyleSpan = toHTMLSpanElement(topNode);
-    if (isListItem(enclosingBlock(insertionPos.anchorNode()))) {
+    const Node* node = insertionPos.anchorNode();
+    // |node| can be an inline element like <br> under <li>
+    // e.g.) editing/execCommand/switch-list-type.html
+    //       editing/deleting/backspace-merge-into-block.html
+    if (node->computedStyle()->display() == INLINE) {
+        node = enclosingBlock(insertionPos.anchorNode());
+        if (!node)
+            return false;
+    }
+
+    if (followBlockElementStyle(node)) {
         fragment.removeNodePreservingChildren(wrappingStyleSpan);
         return true;
     }
 
     // Either there are no style spans in the fragment or a WebKit client has added content to the fragment
     // before inserting it.  Look for and handle style spans after insertion.
     if (!isLegacyAppleHTMLSpanElement(topNode))
         return false;
 
     EditingStyle* styleAtInsertionPos = EditingStyle::create(insertionPos.parentAnchoredEquivalent());
@@ skipping 905 matching lines @@
     visitor->trace(m_startOfInsertedContent);
     visitor->trace(m_endOfInsertedContent);
     visitor->trace(m_insertionStyle);
     visitor->trace(m_documentFragment);
     visitor->trace(m_startOfInsertedRange);
     visitor->trace(m_endOfInsertedRange);
     CompositeEditCommand::trace(visitor);
 }
 
 } // namespace blink