Make CaretBase a DisplayItemClient.

third_party/WebKit/Source/core/editing/FrameCaret.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 97 matching lines @@
     // Start blinking with a black caret. Be sure not to restart if we're
     // already blinking in the right location.
     if (m_caretBlinkTimer.isActive())
         return;
 
     if (double blinkInterval = LayoutTheme::theme().caretBlinkInterval())
         m_caretBlinkTimer.startRepeating(blinkInterval, BLINK_FROM_HERE);
 
     m_shouldPaintCaret = true;
     setCaretRectNeedsUpdate();
-
 }
 
 void FrameCaret::setCaretVisibility(CaretVisibility visibility)
 {
     if (getCaretVisibility() == visibility)
         return;
 
     CaretBase::setCaretVisibility(visibility);
 
     updateAppearance();
@@ skipping 11 matching lines @@
 
 bool FrameCaret::caretPositionIsValidForDocument(const Document& document) const
 {
     if (!isActive())
         return true;
 
     return caretPosition().position().document() == document
         && !caretPosition().position().isOrphan();
 }
 
-void FrameCaret::invalidateCaretRect()
+void FrameCaret::invalidateCaretRect(bool forceInvalidation)
 {
     if (!m_caretRectDirty)
         return;
     m_caretRectDirty = false;
 
     DCHECK(caretPositionIsValidForDocument(*m_frame->document()));
     LayoutObject* layoutObject = nullptr;
     LayoutRect newRect;
     if (isActive())
         newRect = localCaretRectOfPosition(caretPosition(), layoutObject);
     Node* newNode = layoutObject ? layoutObject->node() : nullptr;
 
-    if (!m_caretBlinkTimer.isActive()
+    // It's possible for the timer to be inactive even though we want to
+    // invalidate the caret. For example, when running as a layout test the
+    // caret blink interval could be zero and thus |m_caretBlinkTimer| will
+    // never be started. We provide |forceInvalidation| for use by paint
+    // invalidation internals where we need to invalidate the caret regardless
+    // of timer state.
+    if (!forceInvalidation
+        && !m_caretBlinkTimer.isActive()
         && newNode == m_previousCaretNode
         && newRect == m_previousCaretRect
         && getCaretVisibility() == m_previousCaretVisibility)
         return;
 
     LayoutViewItem view = m_frame->document()->layoutViewItem();
     if (m_previousCaretNode && (shouldRepaintCaret(*m_previousCaretNode) || shouldRepaintCaret(view)))
         invalidateLocalCaretRect(m_previousCaretNode.get(), m_previousCaretRect);
     if (newNode && (shouldRepaintCaret(*newNode) || shouldRepaintCaret(view)))
         invalidateLocalCaretRect(newNode, newRect);
@@ skipping 88 matching lines @@
 void FrameCaret::caretBlinkTimerFired(TimerBase*)
 {
     DCHECK(caretIsVisible());
     if (isCaretBlinkingSuspended() && m_shouldPaintCaret)
         return;
     m_shouldPaintCaret = !m_shouldPaintCaret;
     setCaretRectNeedsUpdate();
 }
 
 } // nemaspace blink