arc: Scale notification surface to fit

ui/arc/notification/arc_custom_notification_view.cc

Index: ui/arc/notification/arc_custom_notification_view.cc
diff --git a/ui/arc/notification/arc_custom_notification_view.cc b/ui/arc/notification/arc_custom_notification_view.cc
index cd5f6c1359a7cf665ef9924cb7b7d0fa42b97b52..9fe3b059bec68d358c5a623d2f9469e57f868892 100644
--- a/ui/arc/notification/arc_custom_notification_view.cc
+++ b/ui/arc/notification/arc_custom_notification_view.cc
@@ -9,6 +9,7 @@
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
+#include "ui/message_center/message_center_style.h"
 #include "ui/resources/grit/ui_resources.h"
 #include "ui/strings/grit/ui_strings.h"
 #include "ui/views/background.h"
@@ -80,17 +81,40 @@ void ArcCustomNotificationView::ViewHierarchyChanged(
   if (!widget || !surface_ || !details.is_add)
     return;
 
-  SetPreferredSize(surface_->GetSize());
+  gfx::Size preferred_size = surface_->GetSize();
+  float scale = 1.0f;
+  if (preferred_size.width() != message_center::kNotificationWidth) {
+    scale = static_cast<float>(message_center::kNotificationWidth) /
+            preferred_size.width();
+    preferred_size.SetSize(message_center::kNotificationWidth,
+                           preferred_size.height() * scale);
+  }
+
+  SetPreferredSize(preferred_size);
   Attach(surface_->window());
 }
 
 void ArcCustomNotificationView::Layout() {
   views::NativeViewHost::Layout();
 
+  if (surface_) {
+    // Scale notification surface if necessary.
+    gfx::Transform transform;
+    const gfx::Size surface_size = surface_->GetSize();
+    const gfx::Size contents_size = GetContentsBounds().size();
+    if (!surface_size.IsEmpty() && !contents_size.IsEmpty() &&
+        surface_size != contents_size) {

[reveman, 2016/07/28 18:50:53]

nit: "surface_size != contents_size" check is not needed

[xiyuan, 2016/07/28 19:32:51]

Done.

+      transform.Scale(
+          static_cast<float>(contents_size.width()) / surface_size.width(),
+          static_cast<float>(contents_size.height()) / surface_size.height());
+    }
+    surface_->window()->SetTransform(transform);
+  }
+
   if (!floating_close_button_widget_ || !surface_ || !GetWidget())
     return;
 
-  gfx::Rect surface_local_bounds(surface_->window()->bounds().size());
+  gfx::Rect surface_local_bounds(surface_->GetSize());
   gfx::Rect close_button_bounds(floating_close_button_->GetPreferredSize());
   close_button_bounds.set_x(surface_local_bounds.right() -
                             close_button_bounds.width());