Add infrastructure for partial layouts

Source/core/rendering/RenderObject.cpp

Index: Source/core/rendering/RenderObject.cpp
diff --git a/Source/core/rendering/RenderObject.cpp b/Source/core/rendering/RenderObject.cpp
index df6b2c140ba600fa9daad7b01964cdd1e031094e..33c16c21ef66f5ed2be9b3a44d59b72a3e2e6e6f 100644
--- a/Source/core/rendering/RenderObject.cpp
+++ b/Source/core/rendering/RenderObject.cpp
@@ -746,6 +746,16 @@ void RenderObject::checkBlockPositionedObjectsNeedLayout()
     if (isRenderBlock())
         toRenderBlock(this)->checkPositionedObjectsNeedLayout();
 }
+
+void RenderObject::checkNotInPartialLayout()
+{
+    if (frame()) {

[esprehn, 2013/08/18 03:43:15]

Add a frameView(), also I don't know how this can be null. Frameless documents
never have renderers.

If it can be null this should be an early return.

[pdr., 2013/08/20 06:19:10]

Done.

I changed this to not even check for null so we'll null deref crash in debug if
our assumption is wrong.

+        if (FrameView* view = frame()->view()) {
+            // During partial layout, setNeedsLayout(true or false) should not be called.
+            ASSERT(!view->shouldStopPartialLayout());
+        }
+    }
+}
 #endif
 
 void RenderObject::setPreferredLogicalWidthsDirty(bool shouldBeDirty, MarkingBehavior markParents)