Invalidate caret during paint invalidation

third_party/WebKit/Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  *               (http://www.torchmobile.com/)
@@ skipping 1496 matching lines @@
 
   // TODO(wangxianzhu): We may avoid subtree paint invalidation on CSS clip
   // change for SPv2.
   if (diff.cssClipChanged())
     diff.setNeedsPaintInvalidationSubtree();
 
   // Optimization: for decoration/color property changes, invalidation is only
   // needed if we have style or text affected by these properties.
   if (diff.textDecorationOrColorChanged() && !diff.needsPaintInvalidation()) {
     if (style()->hasBorder() || style()->hasOutline() ||
-        style()->hasBackgroundRelatedColorReferencingCurrentColor()
+        style()->hasBackgroundRelatedColorReferencingCurrentColor() ||
         // Skip any text nodes that do not contain text boxes. Whitespace cannot
         // be skipped or we will miss invalidating decorations (e.g.,
         // underlines).
-        || (isText() && !isBR() && toLayoutText(this)->hasTextBoxes())
-        // Caret is painted in text color.
-        || (isLayoutBlock() && toLayoutBlock(this)->hasCaret()) ||

[chrishtr, 2017/02/03 02:07:01]

Why can this line go?

[Xianzhu, 2017/02/03 04:31:28]

Now we always check for caret change in each frame in
CaretDisplayItemClient::updateForPaintInvalidation() which is indirectly called
from FrameView::prePaint and FrameView::invalidateTreeIfNeededRecursive(). This
makes all paint invalidations of carets enclosed in CaretDisplayItemClient, with
little additional cost*. Caret color is also checked in
CaretDisplayItemClient::updateForPaintInvalidation().

This is also the reason that some setCaretRectNeedsUpdate calls are removed.

* Actually in many cases the cost is reduced because now we call
CaretDisplayItemClient::computeCaretRect() and
CaretDisplayItemClient::caretLayoutObject() only once in each frame, instead of
many times before.

+        (isText() && !isBR() && toLayoutText(this)->hasTextBoxes()) ||
         (isSVG() && style()->svgStyle().isFillColorCurrentColor()) ||
         (isSVG() && style()->svgStyle().isStrokeColorCurrentColor()) ||
         isListMarker())
       diff.setNeedsPaintInvalidationObject();
   }
 
   // The answer to layerTypeRequired() for plugins, iframes, and canvas can
   // change without the actual style changing, since it depends on whether we
   // decide to composite these elements. When the/ layer status of one of these
   // elements changes, we need to force a layout.
@@ skipping 1965 matching lines @@
     const blink::LayoutObject* root = object1;
     while (root->parent())
       root = root->parent();
     root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
   } else {
     WTFLogAlways("%s", "Cannot showLayoutTree. Root is (nil)");
   }
 }
 
 #endif