views: Update event-related API to use PointF/RectF instead of Point/Rect.

ash/shelf/shelf_button.cc

Index: ash/shelf/shelf_button.cc
diff --git a/ash/shelf/shelf_button.cc b/ash/shelf/shelf_button.cc
index fb255d7fd893814150850f8090c2dafe248a56e1..3b66eea314fd788ccc825722fe63dfe3b9ffbac4 100644
--- a/ash/shelf/shelf_button.cc
+++ b/ash/shelf/shelf_button.cc
@@ -124,7 +124,7 @@ class ShelfButton::BarView : public views::ImageView,
   }
 
   // View
-  virtual bool HitTestRect(const gfx::Rect& rect) const OVERRIDE {
+  virtual bool HitTestRect(const gfx::RectF& rect) const OVERRIDE {
     // Allow Mouse...() messages to go to the parent view.
     return false;
   }
@@ -201,7 +201,7 @@ ShelfButton::IconView::IconView() : icon_size_(kIconSize) {
 ShelfButton::IconView::~IconView() {
 }
 
-bool ShelfButton::IconView::HitTestRect(const gfx::Rect& rect) const {
+bool ShelfButton::IconView::HitTestRect(const gfx::RectF& rect) const {
   // Return false so that ShelfButton gets all the mouse events.
   return false;
 }