Remove obsolete FIXME that no longer applies for blink rendering architecture

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 1656814b743940e98071c60f4aafacabb0e2487e..81251cf3727b46c1d104edbd4925e8186c4fdbf5 100644
--- a/Source/core/rendering/RenderView.cpp
+++ b/Source/core/rendering/RenderView.cpp
@@ -193,8 +193,8 @@ void RenderView::checkLayoutState(const LayoutState& state)
 
 void RenderView::initializeLayoutState(LayoutState& state)
 {
-    // FIXME: May be better to push a clip and avoid issuing offscreen repaints.

[eseidel, 2014/03/11 19:23:54]

Based on what I now understand, we should just remove this FIXME.  We don't
control our viewport, the compositor does.  We paint whatever rects it tells us
to paint, and do not get to implicitly clip our painting based on what we think
the viewport is.

LayoutState's clipped state is used for computing repaint rects, which in turn
are used for layer boundaries.  We are able to pre-paint the root layer for
accelerated scrolling, but we do not yet prepaint any arbitrary overflow: scroll
div, in part due to this clipped state not being aware of prepainting and the
compositor controlling clipping of our layers.

-    state.m_clipped = false;
+    state.m_clipped = true;
+    state.m_clipRect = viewRect();
     state.m_pageLogicalHeight = m_pageLogicalHeight;
     state.m_pageLogicalHeightChanged = m_pageLogicalHeightChanged;
     state.m_isPaginated = state.m_pageLogicalHeight;