Move canonicalPosition() for VisiblePosition to VisibleUnits.cpp

Source/core/editing/VisiblePosition.cpp

Index: Source/core/editing/VisiblePosition.cpp
diff --git a/Source/core/editing/VisiblePosition.cpp b/Source/core/editing/VisiblePosition.cpp
index 44973afe8db45b8b4280c2da9103552eb7fdcef5..e0cde3e3cf9bdb0882792675d4c6f0fa2710ff11 100644
--- a/Source/core/editing/VisiblePosition.cpp
+++ b/Source/core/editing/VisiblePosition.cpp
@@ -463,105 +463,10 @@ VisiblePosition honorEditingBoundaryAtOrAfter(const VisiblePosition& pos, const
     return firstEditableVisiblePositionAfterPositionInRoot(pos.deepEquivalent(), highestRoot);
 }
 
-template <typename PositionType>
-static PositionType canonicalizeCandidate(const PositionType& candidate)
-{
-    if (candidate.isNull())
-        return PositionType();
-    ASSERT(isVisuallyEquivalentCandidate(candidate));
-    PositionType upstream = mostBackwardCaretPosition(candidate);
-    if (isVisuallyEquivalentCandidate(upstream))
-        return upstream;
-    return candidate;
-}
-
-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.
-    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 PositionType();
-
-    ASSERT(position.document());
-    position.document()->updateLayoutIgnorePendingStylesheets();
-
-    Node* node = position.computeContainerNode();
-
-    PositionType candidate = mostBackwardCaretPosition(position);
-    if (isVisuallyEquivalentCandidate(candidate))
-        return candidate;
-    candidate = mostForwardCaretPosition(position);
-    if (isVisuallyEquivalentCandidate(candidate))
-        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.
-    PositionType next = canonicalizeCandidate(nextCandidate(position));
-    PositionType prev = canonicalizeCandidate(previousCandidate(position));
-    Node* nextNode = next.anchorNode();
-    Node* prevNode = prev.anchorNode();
-
-    // 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.anchorNode()->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 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;
-}
-
-Position canonicalPositionOf(const Position& position)
-{
-    return canonicalPosition(position);
-}
-
-PositionInComposedTree canonicalPositionOf(const PositionInComposedTree& position)
-{
-    return canonicalPosition(position);
-}
-
 template<typename Strategy>
 static PositionWithAffinityTemplate<Strategy> visiblePositionOfAlgorithm(const PositionAlgorithm<Strategy>& position, TextAffinity affinity)
 {
-    const PositionAlgorithm<Strategy> deepPosition = canonicalPosition(position);
+    const PositionAlgorithm<Strategy> deepPosition = canonicalPositionOf(position);
     if (deepPosition.isNull())
         return PositionWithAffinityTemplate<Strategy>();
     if (affinity == TextAffinity::Downstream)