Use pixel coordinates for shadow underlay bounds

components/exo/shell_surface.cc

Index: components/exo/shell_surface.cc
diff --git a/components/exo/shell_surface.cc b/components/exo/shell_surface.cc
index d93e6c717f64bf0c8805c77777c344d53006ca53..0127406abcc495f767968f0dded8cb0d90e49050 100644
--- a/components/exo/shell_surface.cc
+++ b/components/exo/shell_surface.cc
@@ -623,6 +623,11 @@ void ShellSurface::SetScale(double scale) {
   TRACE_EVENT1("exo", "ShellSurface::SetScale", "scale", scale);
 
   if (scale <= 0.0) {
+    // TODO(oshima): This uses negative value to tell if android is
+    // NYC, which sends pixel bounds for shadow. Remove this once NYC
+    // transition is complete.
+    pixel_shadow_bounds_ = true;
+    pending_scale_ = -scale;

[oshima, 2017/02/02 00:05:55]

I'm using negative scale during the transition. If you have a better idea how to
distinguish between M vs N, please let me know.

     DLOG(WARNING) << "Surface scale must be greater than 0";
     return;
   }
@@ -1414,10 +1419,18 @@ void ShellSurface::UpdateShadow() {
       shadow_underlay_->Hide();
   } else {
     wm::SetShadowElevation(window, wm::ShadowElevation::MEDIUM);
-
-    gfx::Rect shadow_content_bounds = shadow_content_bounds_;
-    if (shadow_content_bounds.IsEmpty())
-      shadow_content_bounds = window->bounds();
+    gfx::Rect shadow_content_bounds =
+        gfx::ScaleToEnclosedRect(shadow_content_bounds_, 1.f / scale_);
+    gfx::Rect shadow_underlay_bounds = shadow_content_bounds_;
+    if (shadow_underlay_bounds.IsEmpty())
+      shadow_underlay_bounds = gfx::Rect(surface_->window()->bounds().size());
+
+    if (!pixel_shadow_bounds_) {
+      shadow_content_bounds = shadow_content_bounds_;
+      if (shadow_content_bounds.IsEmpty()) {
+        shadow_content_bounds = window->bounds();
+      }
+    }
 
     // TODO(oshima): Adjust the coordinates from client screen to
     // chromeos screen when multi displays are supported.
@@ -1440,8 +1453,16 @@ void ShellSurface::UpdateShadow() {
       shadow_underlay_->Init(ui::LAYER_SOLID_COLOR);
       shadow_underlay_->layer()->SetColor(SK_ColorBLACK);
       DCHECK(shadow_underlay_->layer()->fills_bounds_opaquely());
-      window->AddChild(shadow_underlay_);
-      window->StackChildAtBottom(shadow_underlay_);
+      if (!pixel_shadow_bounds_) {
+        window->AddChild(shadow_underlay_);
+        window->StackChildAtBottom(shadow_underlay_);
+      } else {
+        surface_->window()->AddChild(shadow_underlay_);
+      }
+    }
+
+    if (pixel_shadow_bounds_) {
+      surface_->window()->StackChildAtBottom(shadow_underlay_);
     }
 
     bool underlay_capture_events =
@@ -1459,14 +1480,20 @@ void ShellSurface::UpdateShadow() {
     if ((widget_->IsFullscreen() || underlay_capture_events) &&
         ash::wm::GetWindowState(window)->allow_set_bounds_in_maximized() &&
         window->layer()->GetTargetTransform().IsIdentity()) {
-      gfx::Point origin;
-      origin -= window->bounds().origin().OffsetFromOrigin();
-      shadow_bounds.set_origin(origin);
-      shadow_bounds.set_size(window->parent()->bounds().size());
+      if (!pixel_shadow_bounds_) {
+        gfx::Point origin;
+        origin -= window->bounds().origin().OffsetFromOrigin();
+        shadow_bounds.set_origin(origin);
+        shadow_bounds.set_size(window->parent()->bounds().size());
+      } else {
+        shadow_underlay_bounds = gfx::Rect(surface_->window()->bounds().size());
+      }
       shadow_underlay_opacity = 1.0f;
     }
 
-    gfx::Rect shadow_underlay_bounds = shadow_bounds;
+    if (!pixel_shadow_bounds_) {
+      shadow_underlay_bounds = shadow_bounds;
+    }
 
     // Constrain the underlay bounds to the client area in case shell surface
     // frame is enabled.
@@ -1498,7 +1525,12 @@ void ShellSurface::UpdateShadow() {
       shadow_overlay_->Init(ui::LAYER_NOT_DRAWN);
       shadow_overlay_->layer()->Add(shadow->layer());
       window->AddChild(shadow_overlay_);
-      window->StackChildAbove(shadow_overlay_, shadow_underlay_);
+
+      if (!pixel_shadow_bounds_) {
+        window->StackChildAbove(shadow_overlay_, shadow_underlay_);
+      } else {
+        window->StackChildBelow(shadow_overlay_, surface_->window());
+      }
       shadow_overlay_->Show();
     }
     shadow_overlay_->SetBounds(shadow_bounds);