Introduce positionForPoint() in LocalFrame class as replacement of visiblePositionForPoint()

This patch introduces |positionForPoint()| in |LocalFrame| class as replacement
of |visiblePositionForPoint()| to reduce doing visible position
canonicalization for increasing chance to delay canonicalization with changing
|setPosition()| in |DragCaretController| and |VisibleSelection| constructor to
take |PositionWithAffinity|.

Note: Both of |VisbilePosition| constructor and |VisibleSelection| constructor
do visible position canaonicalization.

This patch is a preparation of making selection to handle granularity for web
component, http://crrev.com/1277863002

BUG=513568
TEST=n/a; no behavior changes

Review URL: https://codereview.chromium.org/1310323004

git-svn-id: svn://svn.chromium.org/blink/trunk@201110 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/editing/DragCaretController.cpp

@@ -47,7 +47,7 @@ bool DragCaretController::isContentRichlyEditable() const
     return isRichlyEditablePosition(m_position.deepEquivalent());
 }
 
-void DragCaretController::setCaretPosition(const VisiblePosition& position)
+void DragCaretController::setCaretPosition(const PositionWithAffinity& position)
 {
     // for querying Layer::compositingState()
     // This code is probably correct, since it doesn't occur in a stack that
@@ -56,7 +56,7 @@ void DragCaretController::setCaretPosition(const VisiblePosition& position)
 
     if (Node* node = m_position.deepEquivalent().anchorNode())
         invalidateCaretRect(node);
-    m_position = position;
+    m_position = VisiblePosition(position);
     Document* document = nullptr;
     if (Node* node = m_position.deepEquivalent().anchorNode()) {
         invalidateCaretRect(node);

third_party/WebKit/Source/core/editing/DragCaretController.h

@@ -44,8 +44,8 @@ public:
 
     bool hasCaret() const { return m_position.isNotNull(); }
     const VisiblePosition& caretPosition() { return m_position; }
-    void setCaretPosition(const VisiblePosition&);
-    void clear() { setCaretPosition(VisiblePosition()); }
+    void setCaretPosition(const PositionWithAffinity&);
+    void clear() { setCaretPosition(PositionWithAffinity()); }
 
     void nodeWillBeRemoved(Node&);
 

third_party/WebKit/Source/core/editing/VisibleSelection.cpp

@@ -70,6 +70,11 @@ VisibleSelection::VisibleSelection(const PositionInComposedTree& base, const Pos
 {
 }
 
+VisibleSelection::VisibleSelection(const PositionWithAffinity& pos, bool isDirectional)
+    : VisibleSelection(pos.position(), pos.affinity(), isDirectional)
+{
+}
+
 VisibleSelection::VisibleSelection(const VisiblePosition& pos, bool isDirectional)
     : VisibleSelection(pos, pos, isDirectional)
 {

third_party/WebKit/Source/core/editing/VisibleSelection.h

@@ -99,6 +99,7 @@ public:
 
     explicit VisibleSelection(const EphemeralRange&, TextAffinity = SEL_DEFAULT_AFFINITY, bool isDirectional = false);
 
+    explicit VisibleSelection(const PositionWithAffinity&, bool isDirectional = false);
     explicit VisibleSelection(const VisiblePosition&, bool isDirectional = false);
     VisibleSelection(const VisiblePosition&, const VisiblePosition&, bool isDirectional = false);
 

third_party/WebKit/Source/core/frame/LocalFrame.cpp

@@ -672,19 +672,19 @@ String LocalFrame::selectedTextForClipboard() const
     return selection().selectedTextForClipboard();
 }
 
-VisiblePosition LocalFrame::visiblePositionForPoint(const IntPoint& framePoint)
+PositionWithAffinity LocalFrame::positionForPoint(const IntPoint& framePoint)
 {
     HitTestResult result = eventHandler().hitTestResultAtPoint(framePoint);
     Node* node = result.innerNodeOrImageMapImage();
     if (!node)
-        return VisiblePosition();
+        return PositionWithAffinity();
     LayoutObject* layoutObject = node->layoutObject();
     if (!layoutObject)
-        return VisiblePosition();
-    VisiblePosition visiblePos = VisiblePosition(layoutObject->positionForPoint(result.localPoint()));
-    if (visiblePos.isNull())
-        visiblePos = VisiblePosition(firstPositionInOrBeforeNode(node));
-    return visiblePos;
+        return PositionWithAffinity();
+    const PositionWithAffinity position = layoutObject->positionForPoint(result.localPoint());
+    if (position.isNull())
+        return PositionWithAffinity(firstPositionInOrBeforeNode(node));
+    return position;
 }
 
 Document* LocalFrame::documentAtPoint(const IntPoint& pointInRootFrame)
@@ -702,10 +702,11 @@ Document* LocalFrame::documentAtPoint(const IntPoint& pointInRootFrame)
 
 EphemeralRange LocalFrame::rangeForPoint(const IntPoint& framePoint)
 {
-    VisiblePosition position = visiblePositionForPoint(framePoint);
-    if (position.isNull())
+    const PositionWithAffinity positionWithAffinity = positionForPoint(framePoint);
+    if (positionWithAffinity.isNull())
         return EphemeralRange();
 
+    VisiblePosition position(positionWithAffinity);
     VisiblePosition previous = position.previous();
     if (previous.isNotNull()) {
         const EphemeralRange previousCharacterRange = makeRange(previous, position);

third_party/WebKit/Source/core/frame/LocalFrame.h

@@ -72,7 +72,7 @@ class TreeScope;
 class ScriptController;
 class SpellChecker;
 class TreeScope;
-class VisiblePosition;
+template <typename Strategy> class PositionWithAffinityTemplate;
 
 class CORE_EXPORT LocalFrame : public Frame, public LocalFrameLifecycleNotifier, public WillBeHeapSupplementable<LocalFrame> {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(LocalFrame);
@@ -159,7 +159,7 @@ public:
     String selectedText() const;
     String selectedTextForClipboard() const;
 
-    VisiblePosition visiblePositionForPoint(const IntPoint& framePoint);
+    PositionWithAffinityTemplate<EditingAlgorithm<NodeTraversal>> positionForPoint(const IntPoint& framePoint);
     Document* documentAtPoint(const IntPoint& windowPoint);
     EphemeralRangeTemplate<EditingAlgorithm<NodeTraversal>> rangeForPoint(const IntPoint& framePoint);
 

third_party/WebKit/Source/core/page/DragController.cpp

@@ -374,7 +374,7 @@ bool DragController::tryDocumentDrag(DragData* dragData, DragDestinationAction a
         }
 
         if (!m_fileInputElementUnderMouse)
-            m_page->dragCaretController().setCaretPosition(m_documentUnderMouse->frame()->visiblePositionForPoint(point));
+            m_page->dragCaretController().setCaretPosition(m_documentUnderMouse->frame()->positionForPoint(point));
 
         LocalFrame* innerFrame = element->document().frame();
         dragSession.operation = dragIsMove(innerFrame->selection(), dragData) ? DragOperationMove : DragOperationCopy;
@@ -428,7 +428,7 @@ static bool setSelectionToDragCaret(LocalFrame* frame, VisibleSelection& dragCar
 {
     frame->selection().setSelection(dragCaret);
     if (frame->selection().isNone()) {
-        dragCaret = VisibleSelection(frame->visiblePositionForPoint(point));
+        dragCaret = VisibleSelection(frame->positionForPoint(point));
         frame->selection().setSelection(dragCaret);
         range = dragCaret.toNormalizedRange();
     }