FrameSelection::updateApperance for caret should not cause layout.

Source/core/editing/FrameSelection.cpp

 /*
  * Copyright (C) 2004, 2008, 2009, 2010 Apple 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 254 matching lines @@
 
     VisibleSelection oldSelection = m_selection;
 
     m_selection = s;
     setCaretRectNeedsUpdate();
 
     if (!s.isNone() && !(options & DoNotSetFocus))
         setFocusedNodeIfNeeded();
 
     if (!(options & DoNotUpdateAppearance)) {
-        m_frame->document()->updateLayoutIgnorePendingStylesheets();
-
         // Hits in compositing/overflow/do-not-paint-outline-into-composited-scrolling-contents.html
         DisableCompositingQueryAsserts disabler;
         updateAppearance();
     }
 
     // Always clear the x position used for vertical arrow navigation.
     // It will be restored by the vertical arrow navigation code if necessary.
     m_xPosForVerticalArrowNavigation = NoXPosForVerticalArrowNavigation();
     selectFrameElementInParentIfFullySelected();
     notifyRendererOfSelectionChange(userTriggered);
@@ skipping 939 matching lines @@
 }
 
 static bool isTextFormControl(const VisibleSelection& selection)
 {
     return enclosingTextFormControl(selection.start());
 }
 
 LayoutRect FrameSelection::localCaretRect()
 {
     if (shouldUpdateCaretRect()) {
-        if (!isNonOrphanedCaret(m_selection))
+        if (!isNonOrphanedCaret(m_selection)) {
             clearCaretRect();
-        else if (isTextFormControl(m_selection))
+        } else if (isTextFormControl(m_selection)) {
+            m_frame->document()->updateLayoutIgnorePendingStylesheets();
             m_absCaretBoundsDirty |= updateCaretRect(m_frame->document(), PositionWithAffinity(m_selection.start().isCandidate() ? m_selection.start() : Position(), m_selection.affinity()));
-        else
+        } else {
             m_absCaretBoundsDirty |= updateCaretRect(m_frame->document(), VisiblePosition(m_selection.start(), m_selection.affinity()));
+        }
     }
 
     return localCaretRectWithoutUpdate();
 }
 
 IntRect FrameSelection::absoluteCaretBounds()
 {
     recomputeCaretRect();
     return m_absCaretBounds;
 }
@@ skipping 33 matching lines @@
 void FrameSelection::invalidateCaretRect()
 {
     if (!isCaret())
         return;
 
     CaretBase::invalidateCaretRect(m_selection.start().deprecatedNode(), recomputeCaretRect());
 }
 
 void FrameSelection::paintCaret(GraphicsContext* context, const LayoutPoint& paintOffset, const LayoutRect& clipRect)
 {
-    if (m_selection.isCaret() && m_caretPaint)
+    if (m_selection.isCaret() && m_caretPaint) {
+        localCaretRect();

[yosin_UTC9, 2014/08/04 01:44:23]

The name of |localCaretRect()| make me to feel it is a function without side
effect, but it updates |m_absCaretBoundsDirty|. It is better to rename it?

[yoichio, 2014/08/04 02:12:18]

Done.

         CaretBase::paintCaret(m_selection.start().deprecatedNode(), context, paintOffset, clipRect);
+    }
 }
 
 bool FrameSelection::contains(const LayoutPoint& point)
 {
     Document* document = m_frame->document();
 
     // Treat a collapsed selection like no selection.
     if (!isRange())
         return false;
     if (!document->renderView())
@@ skipping 228 matching lines @@
     return m_focused && m_frame->page() && m_frame->page()->focusController().isActive();
 }
 
 inline static bool shouldStopBlinkingDueToTypingCommand(LocalFrame* frame)
 {
     return frame->editor().lastEditCommand() && frame->editor().lastEditCommand()->shouldStopCaretBlinking();
 }
 
 void FrameSelection::updateAppearance()
 {
+    bool isTextForm = isTextFormControl(m_selection);
     // Paint a block cursor instead of a caret in overtype mode unless the caret is at the end of a line (in this case
     // the FrameSelection will paint a blinking caret as usual).
     VisiblePosition forwardPosition;
     if (m_shouldShowBlockCursor && m_selection.isCaret()) {
         forwardPosition = modifyExtendingForward(CharacterGranularity);
         m_caretPaint = forwardPosition.isNull();
     }
 
-    bool caretRectChangedOrCleared = recomputeCaretRect();
+    bool caretRectChangedOrCleared = isTextForm || recomputeCaretRect();
     bool shouldBlink = shouldBlinkCaret() && forwardPosition.isNull();
 
     // If the caret moved, stop the blink timer so we can restart with a
     // black caret in the new location.
     if (caretRectChangedOrCleared || !shouldBlink || shouldStopBlinkingDueToTypingCommand(m_frame)) {
         m_caretBlinkTimer.stop();
         if (!shouldBlink && m_caretPaint) {
             m_caretPaint = false;
             invalidateCaretRect();
         }
@@ skipping 10 matching lines @@
             invalidateCaretRect();
         }
     }
 
     RenderView* view = m_frame->contentRenderer();
     if (!view)
         return;
 
     // Construct a new VisibleSolution, since m_selection is not necessarily valid, and the following steps
     // assume a valid selection. See <https://bugs.webkit.org/show_bug.cgi?id=69563> and <rdar://problem/10232866>.
-    VisibleSelection selection(m_selection.visibleStart(), forwardPosition.isNotNull() ? forwardPosition : m_selection.visibleEnd());
+    VisibleSelection selection;
+    if (isTextForm)
+        selection.setWithoutValidation(m_selection.start(), forwardPosition.isNotNull() ? forwardPosition.deepEquivalent() : m_selection.end());
+    else
+        selection = VisibleSelection(m_selection.visibleStart(), forwardPosition.isNotNull() ? forwardPosition : m_selection.visibleEnd());
 
     if (!selection.isRange()) {
         view->clearSelection();
         return;
     }
 
     // Use the rightmost candidate for the start of the selection, and the leftmost candidate for the end of the selection.
     // Example: foo <a>bar</a>.  Imagine that a line wrap occurs after 'foo', and that 'bar' is selected.   If we pass [foo, 3]
     // as the start of the selection, the selection painting code will think that content on the line containing 'foo' is selected
     // and will fill the gap before 'bar'.
@@ skipping 55 matching lines @@
     ASSERT(caretIsVisible());
     ASSERT(isCaret());
     if (isCaretBlinkingSuspended() && m_caretPaint)
         return;
     m_caretPaint = !m_caretPaint;
     invalidateCaretRect();
 }
 
 void FrameSelection::notifyRendererOfSelectionChange(EUserTriggered userTriggered)
 {
-    m_frame->document()->updateRenderTreeIfNeeded();
-
     if (HTMLTextFormControlElement* textControl = enclosingTextFormControl(start()))
         textControl->selectionChanged(userTriggered == UserTriggered);
 }
 
 // Helper function that tells whether a particular node is an element that has an entire
 // LocalFrame and FrameView, a <frame>, <iframe>, or <object>.
 static bool isFrameElement(const Node* n)
 {
     if (!n)
         return false;
@@ skipping 255 matching lines @@
     sel.showTreeForThis();
 }
 
 void showTree(const blink::FrameSelection* sel)
 {
     if (sel)
         sel->showTreeForThis();
 }
 
 #endif