views: Make view::Views::GetPreferredSize() const.

ash/ime/infolist_window.cc

Index: ash/ime/infolist_window.cc
diff --git a/ash/ime/infolist_window.cc b/ash/ime/infolist_window.cc
index c29d623b074b6dd109792cc6e8612f2ce64bcabc..429cca59f75ba0772e489515c3bcb4a6d5d98c2e 100644
--- a/ash/ime/infolist_window.cc
+++ b/ash/ime/infolist_window.cc
@@ -94,7 +94,7 @@ class InfolistEntryView : public views::View {
 
  private:
   // views::View implementation.
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
 
   void UpdateBackground();
 
@@ -143,7 +143,7 @@ void InfolistEntryView::SetEntry(const ui::InfolistEntry& entry) {
   UpdateBackground();
 }
 
-gfx::Size InfolistEntryView::GetPreferredSize() {
+gfx::Size InfolistEntryView::GetPreferredSize() const {
   return gfx::Size(kInfolistEntryWidth, GetHeightForWidth(kInfolistEntryWidth));
 }