Convert some call sites to use explicit LayoutRect->FloatRect conversion.

Source/core/paint/DeprecatedPaintLayerClipper.cpp

Index: Source/core/paint/DeprecatedPaintLayerClipper.cpp
diff --git a/Source/core/paint/DeprecatedPaintLayerClipper.cpp b/Source/core/paint/DeprecatedPaintLayerClipper.cpp
index 4172bd88a7e7c9f92580965e6ae97b3c3a9da252..1d0ea54eb3f87d220fef170844a9e2487d983156 100644
--- a/Source/core/paint/DeprecatedPaintLayerClipper.cpp
+++ b/Source/core/paint/DeprecatedPaintLayerClipper.cpp
@@ -82,7 +82,7 @@ LayoutRect DeprecatedPaintLayerClipper::childrenClipRect() const
     // Need to use uncached clip rects, because the value of 'dontClipToOverflow' may be different from the painting path (<rdar://problem/11844909>).
     ClipRectsContext context(clippingRootLayer, UncachedClipRects);
     calculateRects(context, LayoutRect(m_layoutObject.view()->unscaledDocumentRect()), layerBounds, backgroundRect, foregroundRect, outlineRect);
-    return LayoutRect(clippingRootLayer->layoutObject()->localToAbsoluteQuad(FloatQuad(foregroundRect.rect())).enclosingBoundingBox());
+    return LayoutRect(clippingRootLayer->layoutObject()->localToAbsoluteQuad(FloatQuad(FloatRect(foregroundRect.rect()))).enclosingBoundingBox());
 }
 
 LayoutRect DeprecatedPaintLayerClipper::localClipRect() const
@@ -95,7 +95,7 @@ LayoutRect DeprecatedPaintLayerClipper::localClipRect() const
     calculateRects(context, LayoutRect(LayoutRect::infiniteIntRect()), layerBounds, backgroundRect, foregroundRect, outlineRect);
 
     LayoutRect clipRect = backgroundRect.rect();
-    if (clipRect == LayoutRect::infiniteIntRect())
+    if (IntRect(clipRect) == LayoutRect::infiniteIntRect())

[eae, 2015/08/25 17:47:17]

This looks odd, why would we compare a LayoutRect against InfinitIntRect? Could
you file a bug and/or add a TODO comment here?

[chrishtr, 2015/08/25 18:30:44]

The presence of this weird code is already tracked in crbug.com/440143. See the
definition of LayoutRect::infiniteRect().

         return clipRect;
 
     LayoutPoint clippingRootOffset;