Declares GetHeightForWidth() for those who need it.

ash/system/power/power_status_view.cc

Index: ash/system/power/power_status_view.cc
diff --git a/ash/system/power/power_status_view.cc b/ash/system/power/power_status_view.cc
index a268d3a2c147da7a859dec0712f10072fc28fe42..78409aefe6f793644630d8eea1195a007d053cbb 100644
--- a/ash/system/power/power_status_view.cc
+++ b/ash/system/power/power_status_view.cc
@@ -290,6 +290,10 @@ gfx::Size PowerStatusView::GetPreferredSize() {
   return gfx::Size(size.width(), kTrayPopupItemHeight);
 }
 
+int PowerStatusView::GetHeightForWidth(int width) {
+  return kTrayPopupItemHeight;
+}
+
 void PowerStatusView::Layout() {
   views::View::Layout();