[ash-md] Hides frame headers in overview mode not using a mask

ash/wm/panels/panel_frame_view.cc

Index: ash/wm/panels/panel_frame_view.cc
diff --git a/ash/wm/panels/panel_frame_view.cc b/ash/wm/panels/panel_frame_view.cc
index 85846f490c70c82d5590915358ed587dc2da0f1f..edaf8a3ee98e639e3321f575e8f9930e018b5683 100644
--- a/ash/wm/panels/panel_frame_view.cc
+++ b/ash/wm/panels/panel_frame_view.cc
@@ -4,6 +4,8 @@
 
 #include "ash/wm/panels/panel_frame_view.h"
 
+#include "ash/common/material_design/material_design_controller.h"
+#include "ash/common/wm_shell.h"
 #include "ash/frame/caption_buttons/frame_caption_button_container_view.h"
 #include "ash/frame/default_header_painter.h"
 #include "ash/frame/frame_border_hit_test_controller.h"
@@ -29,9 +31,12 @@ PanelFrameView::PanelFrameView(views::Widget* frame, FrameType frame_type)
   DCHECK(!frame_->widget_delegate()->CanMaximize());
   if (frame_type != FRAME_NONE)
     InitHeaderPainter();
+  ash::WmShell::Get()->AddShellObserver(this);
 }
 
-PanelFrameView::~PanelFrameView() {}
+PanelFrameView::~PanelFrameView() {
+  ash::WmShell::Get()->RemoveShellObserver(this);
+}
 
 void PanelFrameView::SetFrameColors(SkColor active_frame_color,
                                     SkColor inactive_frame_color) {
@@ -137,4 +142,17 @@ gfx::Rect PanelFrameView::GetWindowBoundsForClientBounds(
   return window_bounds;
 }
 
+///////////////////////////////////////////////////////////////////////////////
+// ShellObserver:
+
+void PanelFrameView::OnOverviewModeStarting() {
+  if (ash::MaterialDesignController::IsOverviewMaterial())
+    SetVisible(false);
+}
+
+void PanelFrameView::OnOverviewModeEnded() {
+  if (ash::MaterialDesignController::IsOverviewMaterial())
+    SetVisible(true);
+}
+
 }  // namespace ash