Blink changes to record interest rects for http://w3c.github.io/frame-timing/

Source/core/rendering/RenderView.cpp

Index: Source/core/rendering/RenderView.cpp
diff --git a/Source/core/rendering/RenderView.cpp b/Source/core/rendering/RenderView.cpp
index 55b16e741275b455a4eb3547caa2a5cae790331c..0d9dfd5ed81cff2c4cd781d687a373bca3074b5b 100644
--- a/Source/core/rendering/RenderView.cpp
+++ b/Source/core/rendering/RenderView.cpp
@@ -333,6 +333,29 @@ void RenderView::invalidateTreeIfNeeded(const PaintInvalidationState& paintInval
     RenderBlock::invalidateTreeIfNeeded(paintInvalidationState);
 }
 
+LayoutRect RenderView::rectForPaintInvalidation(const LayoutRect* paintInvalidationRectPtr) const

[enne (OOO), 2015/02/10 00:17:49]

I see your comment about this existing before and then being removed, but I
think you should investigate where it went.  I would worry about this function
becoming invisibly stale over time as paint code changes, so it'd be better if
you could reuse real functionality elsewhere rather than having this one-off.

[MikeB, 2015/03/18 21:18:34]

I updated this to be more in-line with using properties of LayoutView and not a
dedicated member function, please take a look at WebViewImpl.cpp for details.

+{
+    LayoutRect paintInvalidationRect =
+        paintInvalidationRectPtr ? *paintInvalidationRectPtr : viewRect();
+    Element* owner = document().ownerElement();
+    if (document().printing() || !m_frameView
+        || layer()->compositingState() == PaintsIntoOwnBacking || !owner)
+        return paintInvalidationRect;
+    if (RenderBox* obj = owner->renderBox()) {
+        // Intersect the viewport with the paint invalidation rect.
+        LayoutRect viewRectangle = viewRect();
+        LayoutRect rectToInvalidate = intersection(paintInvalidationRect, viewRectangle);
+
+        // Adjust for scroll offset of the view.
+        rectToInvalidate.moveBy(-viewRectangle.location());
+
+        // Adjust for frame border.
+        rectToInvalidate.moveBy(obj->contentBoxRect().location());
+        return rectToInvalidate;
+    }
+    return paintInvalidationRect;
+}
+
 void RenderView::invalidatePaintForRectangle(const LayoutRect& paintInvalidationRect, PaintInvalidationReason invalidationReason) const
 {
     ASSERT(!paintInvalidationRect.isEmpty());