Templatize canonicalPosition() in VisiblePosition

Source/core/editing/VisiblePosition.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Portions Copyright (c) 2011 Motorola Mobility, 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 530 matching lines @@
 {
     if (candidate.isNull())
         return PositionType();
     ASSERT(candidate.isCandidate());
     PositionType upstream = candidate.upstream();
     if (upstream.isCandidate())
         return upstream;
     return candidate;
 }
 
-static Position canonicalPosition(const Position& passedPosition)
+template <typename PositionType>
+static PositionType canonicalPosition(const PositionType& passedPosition)
 {
     // Sometimes updating selection positions can be extremely expensive and occur
     // frequently.  Often calling preventDefault on mousedown events can avoid
     // doing unnecessary text selection work.  http://crbug.com/472258.
     TRACE_EVENT0("blink", "VisiblePosition::canonicalPosition");
 
     // The updateLayout call below can do so much that even the position passed
     // in to us might get changed as a side effect. Specifically, there are code
     // paths that pass selection endpoints, and updateLayout can change the selection.
-    Position position = passedPosition;
+    PositionType position = passedPosition;
 
     // FIXME (9535):  Canonicalizing to the leftmost candidate means that if we're at a line wrap, we will
     // ask layoutObjects to paint downstream carets for other layoutObjects.
     // To fix this, we need to either a) add code to all paintCarets to pass the responsibility off to
     // the appropriate layoutObject for VisiblePosition's like these, or b) canonicalize to the rightmost candidate
     // unless the affinity is upstream.
     if (position.isNull())
-        return Position();
+        return PositionType();
 
     ASSERT(position.document());
     position.document()->updateLayoutIgnorePendingStylesheets();
 
     Node* node = position.containerNode();
 
-    Position candidate = position.upstream();
+    PositionType candidate = position.upstream();
     if (candidate.isCandidate())
         return candidate;
     candidate = position.downstream();
     if (candidate.isCandidate())
         return candidate;
 
     // When neither upstream or downstream gets us to a candidate (upstream/downstream won't leave
     // blocks or enter new ones), we search forward and backward until we find one.
-    Position next = canonicalizeCandidate(nextCandidate(position));
-    Position prev = canonicalizeCandidate(previousCandidate(position));
+    PositionType next = canonicalizeCandidate(nextCandidate(position));
+    PositionType prev = canonicalizeCandidate(previousCandidate(position));
     Node* nextNode = next.deprecatedNode();
     Node* prevNode = prev.deprecatedNode();
 
     // The new position must be in the same editable element. Enforce that first.
     // Unless the descent is from a non-editable html element to an editable body.
     if (isHTMLHtmlElement(node) && !node->hasEditableStyle() && node->document().body() && node->document().body()->hasEditableStyle())
         return next.isNotNull() ? next : prev;
 
     Element* editingRoot = editableRootForPosition(position);
 
     // If the html element is editable, descending into its body will look like a descent
     // from non-editable to editable content since rootEditableElement() always stops at the body.
     if (isHTMLHtmlElement(editingRoot) || position.deprecatedNode()->isDocumentNode())
         return next.isNotNull() ? next : prev;
 
     bool prevIsInSameEditableElement = prevNode && editableRootForPosition(prev) == editingRoot;
     bool nextIsInSameEditableElement = nextNode && editableRootForPosition(next) == editingRoot;
     if (prevIsInSameEditableElement && !nextIsInSameEditableElement)
         return prev;
 
     if (nextIsInSameEditableElement && !prevIsInSameEditableElement)
         return next;
 
     if (!nextIsInSameEditableElement && !prevIsInSameEditableElement)
-        return Position();
+        return PositionType();
 
     // The new position should be in the same block flow element. Favor that.
     Element* originalBlock = node ? enclosingBlockFlowElement(*node) : 0;
     bool nextIsOutsideOriginalBlock = !nextNode->isDescendantOf(originalBlock) && nextNode != originalBlock;
     bool prevIsOutsideOriginalBlock = !prevNode->isDescendantOf(originalBlock) && prevNode != originalBlock;
     if (nextIsOutsideOriginalBlock && !prevIsOutsideOriginalBlock)
         return prev;
 
     return next;
 }
@@ skipping 176 matching lines @@
     else
         fprintf(stderr, "Cannot showTree for (nil) VisiblePosition.\n");
 }
 
 void showTree(const blink::VisiblePosition& vpos)
 {
     vpos.showTreeForThis();
 }
 
 #endif