exo: Add "back" button to shell surface decorations.

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 29f67496fd02f5be81fcb5141eee5ee1f297c33f..879d3bfc2487d59d131f26d950e79bb1712e11f3 100644
--- a/components/exo/shell_surface.cc
+++ b/components/exo/shell_surface.cc
@@ -4,6 +4,8 @@
 
 #include "components/exo/shell_surface.h"
 
+#include "ash/frame/caption_buttons/frame_caption_button.h"
+#include "ash/frame/custom_frame_view_ash.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "base/logging.h"
@@ -11,6 +13,7 @@
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "components/exo/surface.h"
+#include "grit/ash_resources.h"
 #include "ui/aura/window.h"
 #include "ui/base/hit_test.h"
 #include "ui/views/widget/widget.h"
@@ -18,29 +21,27 @@
 namespace exo {
 namespace {
 
-class CustomFrameView : public views::NonClientFrameView {
+class CustomFrameView : public ash::CustomFrameViewAsh,
+                        public views::ButtonListener {
  public:
-  explicit CustomFrameView(views::Widget* widget) : widget_(widget) {}
+  explicit CustomFrameView(views::Widget* widget)
+      : ash::CustomFrameViewAsh(widget) {
+    ash::FrameCaptionButton* back_button =
+        new ash::FrameCaptionButton(this, ash::CAPTION_BUTTON_ICON_BACK);
+    back_button->SetImages(
+        ash::CAPTION_BUTTON_ICON_BACK, ash::FrameCaptionButton::ANIMATE_NO,
+        IDR_AURA_WINDOW_CONTROL_ICON_BACK, IDR_AURA_WINDOW_CONTROL_BACKGROUND_H,
+        IDR_AURA_WINDOW_CONTROL_BACKGROUND_P);
+    SetLeftCaptionButton(back_button);
+  }
   ~CustomFrameView() override {}
 
-  // Overridden from views::NonClientFrameView:
-  gfx::Rect GetBoundsForClientView() const override { return bounds(); }
-  gfx::Rect GetWindowBoundsForClientBounds(
-      const gfx::Rect& client_bounds) const override {
-    return client_bounds;
-  }
-  int NonClientHitTest(const gfx::Point& point) override {
-    return widget_->client_view()->NonClientHitTest(point);
+  // Overridden from views::ButtonListener:
+  void ButtonPressed(views::Button* sender, const ui::Event& event) override {
+    NOTIMPLEMENTED();
   }
-  void GetWindowMask(const gfx::Size& size, gfx::Path* window_mask) override {}
-  void ResetWindowControls() override {}
-  void UpdateWindowIcon() override {}
-  void UpdateWindowTitle() override {}
-  void SizeConstraintsChanged() override {}
 
  private:
-  views::Widget* const widget_;
-
   DISALLOW_COPY_AND_ASSIGN(CustomFrameView);
 };