gfx: Remove implicit conversions from gfx::Rect to gfx::RectF.

ui/gfx/geometry/rect_f.h

Index: ui/gfx/geometry/rect_f.h
diff --git a/ui/gfx/geometry/rect_f.h b/ui/gfx/geometry/rect_f.h
index 3b132667e40d321f3b0e6b0d74c1495612844af7..703ad0b1ed0c2e350afd0aa45ef36acd52167b1e 100644
--- a/ui/gfx/geometry/rect_f.h
+++ b/ui/gfx/geometry/rect_f.h
@@ -9,6 +9,7 @@
 #include <string>
 
 #include "ui/gfx/geometry/point_f.h"
+#include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size_f.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 
@@ -31,6 +32,13 @@ class GFX_EXPORT RectF {
   RectF(const PointF& origin, const SizeF& size)
       : origin_(origin), size_(size) {}
 
+  explicit RectF(const Rect& r)
+      // TODO(danakj): Change these to checked_cast?
+      : RectF(static_cast<float>(r.x()),
+              static_cast<float>(r.y()),
+              static_cast<float>(r.width()),
+              static_cast<float>(r.height())) {}
+
 #if defined(OS_MACOSX)
   explicit RectF(const CGRect& r);
   // Construct an equivalent CoreGraphics object.