Mash: Show app icons in shelf based on the Widget's app icon

* Use the large icon from WidgetDelegate::GetWindowAppIcon().
* In the mojo app's NativeWidgetMus, serialize the icon's SkBitmap as a vector of bytes and set it as a shared window property.
* In the window manager, pass the serialized icon to any UserWindowObservers.
* In the system UI, deserialize the icon and use it on the shelf.
* Set an icon in task_viewer as a demonstration.

The window property serialization is handled by a custom TypeConverter for vector<uint8>, SkBitmap. In the future it would be nice to use the serialized form of the Skia Mojom struct skia.Bitmap, but that will require Mojo to generate a public API to read the serialized bytes.

Also fixed an issue where the app's primary widget and the window manager's non-client-frame widget would fight over window titles.

A screenshot of the shelf is attached to the bug.

BUG=595850
TEST=launch mash, run mojo:task_viewer, note QuickLaunch shelf icon is default but TaskViewer icon is a gear

Review URL: https://codereview.chromium.org/1824183002

Cr-Commit-Position: refs/heads/master@{#383312}

7 files changed, 57 insertions, 15 deletions

diff --git a/mash/task_viewer/BUILD.gn b/mash/task_viewer/BUILD.gn
index 1d20b22..1ea8cbc 100644
--- a/mash/task_viewer/BUILD.gn
+++ b/mash/task_viewer/BUILD.gn
@@ -21,6 +21,7 @@ source_set("lib") {
     "//mojo/shell/public/cpp",
     "//mojo/shell/public/cpp:sources",
     "//mojo/shell/public/interfaces",
+    "//ui/resources",
     "//ui/views",
     "//ui/views/mus:for_mojo_application",
   ]
diff --git a/mash/task_viewer/task_viewer.cc b/mash/task_viewer/task_viewer.cc
index 0e01a00..fb5cb1f 100644
--- a/mash/task_viewer/task_viewer.cc
+++ b/mash/task_viewer/task_viewer.cc
@@ -19,6 +19,8 @@
 #include "mojo/shell/public/cpp/connector.h"
 #include "mojo/shell/public/interfaces/shell.mojom.h"
 #include "ui/base/models/table_model.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/resources/grit/ui_resources.h"
 #include "ui/views/background.h"
 #include "ui/views/controls/button/label_button.h"
 #include "ui/views/controls/table/table_view.h"
@@ -87,6 +89,13 @@ class TaskViewerContents : public views::WidgetDelegateView,
     return base::ASCIIToUTF16("Tasks");
   }
 
+  gfx::ImageSkia GetWindowAppIcon() override {
+    // TODO(jamescook): Create a new .pak file for this app and make a custom
+    // icon, perhaps one that looks like the Chrome OS task viewer icon.
+    ResourceBundle& rb = ResourceBundle::GetSharedInstance();
+    return *rb.GetImageSkiaNamed(IDR_NOTIFICATION_SETTINGS);
+  }
+
   // Overridden from views::View:
   void Layout() override {
     gfx::Rect bounds = GetLocalBounds();
diff --git a/mash/wm/non_client_frame_controller.cc b/mash/wm/non_client_frame_controller.cc
index ed6ad3a..774329a 100644
--- a/mash/wm/non_client_frame_controller.cc
+++ b/mash/wm/non_client_frame_controller.cc
@@ -125,6 +125,14 @@ class WmNativeWidgetMus : public views::NativeWidgetMus {
   void CenterWindow(const gfx::Size& size) override {
     // Do nothing. The client controls the size, not us.
   }
+  bool SetWindowTitle(const base::string16& title) override {
+    // Do nothing. The client controls the window title, not us.
+    return false;
+  }
+  void SetWindowIcons(const gfx::ImageSkia& window_icon,
+                      const gfx::ImageSkia& app_icon) override {
+    // Do nothing. The client controls window icons, not us.
+  }
   void UpdateClientArea() override {
     // This pushes the client area to the WS. We don't want to do that as
     // the client area should come from the client, not us.
diff --git a/mash/wm/public/interfaces/user_window_controller.mojom b/mash/wm/public/interfaces/user_window_controller.mojom
index c1d61d8..3d84fb1 100644
--- a/mash/wm/public/interfaces/user_window_controller.mojom
+++ b/mash/wm/public/interfaces/user_window_controller.mojom
@@ -8,6 +8,7 @@ struct UserWindow {
   uint32 window_id;
   string window_title;
   bool window_has_focus;
+  array<uint8> window_app_icon;  // Serialized SkBitmap.
 };
 
 // An observer of user windows within mojom::Container::USER_WINDOWS.
@@ -20,6 +21,9 @@ interface UserWindowObserver {
   OnUserWindowRemoved(uint32 window_id);
 
   OnUserWindowTitleChanged(uint32 window_id, string window_title);
+  
+  // |app_icon| is a serialized SkBitmap.
+  OnUserWindowAppIconChanged(uint32 window_id, array<uint8> app_icon);
 
   OnUserWindowFocusChanged(uint32 window_id, bool has_focus);
 };
diff --git a/mash/wm/user_window_controller_impl.cc b/mash/wm/user_window_controller_impl.cc
index be2f24e..3e81da94 100644
--- a/mash/wm/user_window_controller_impl.cc
+++ b/mash/wm/user_window_controller_impl.cc
@@ -11,6 +11,7 @@
 #include "mash/wm/public/interfaces/container.mojom.h"
 #include "mash/wm/root_window_controller.h"
 #include "mojo/common/common_type_converters.h"
+#include "ui/resources/grit/ui_resources.h"
 
 namespace mash {
 namespace wm {
@@ -26,6 +27,17 @@ mojo::String GetWindowTitle(mus::Window* window) {
   return mojo::String(std::string());
 }
 
+// Get the serialized app icon bitmap from a mus::Window.
+mojo::Array<uint8_t> GetWindowAppIcon(mus::Window* window) {
+  if (window->HasSharedProperty(
+          mus::mojom::WindowManager::kWindowAppIcon_Property)) {
+    return mojo::Array<uint8_t>::From(
+        window->GetSharedProperty<const std::vector<uint8_t>>(
+            mus::mojom::WindowManager::kWindowAppIcon_Property));
+  }
+  return mojo::Array<uint8_t>();
+}
+
 // Returns |window|, or an ancestor thereof, parented to |container|, or null.
 mus::Window* GetTopLevelWindow(mus::Window* window, mus::Window* container) {
   while (window && window->parent() != container)
@@ -38,6 +50,7 @@ mojom::UserWindowPtr GetUserWindow(mus::Window* window) {
   mojom::UserWindowPtr user_window(mojom::UserWindow::New());
   user_window->window_id = window->id();
   user_window->window_title = GetWindowTitle(window);
+  user_window->window_app_icon = GetWindowAppIcon(window);
   mus::Window* focused = window->connection()->GetFocusedWindow();
   focused = GetTopLevelWindow(focused, window->parent());
   user_window->window_has_focus = focused == window;
@@ -46,13 +59,14 @@ mojom::UserWindowPtr GetUserWindow(mus::Window* window) {
 
 }  // namespace
 
-// Observes title changes on user windows. UserWindowControllerImpl uses this
-// separate observer to avoid observing duplicate tree change notifications.
-class WindowTitleObserver : public mus::WindowObserver {
+// Observes property changes on user windows. UserWindowControllerImpl uses
+// this separate observer to avoid observing duplicate tree change
+// notifications.
+class WindowPropertyObserver : public mus::WindowObserver {
  public:
-  explicit WindowTitleObserver(UserWindowControllerImpl* controller)
+  explicit WindowPropertyObserver(UserWindowControllerImpl* controller)
       : controller_(controller) {}
-  ~WindowTitleObserver() override {}
+  ~WindowPropertyObserver() override {}
 
  private:
   // mus::WindowObserver:
@@ -61,15 +75,20 @@ class WindowTitleObserver : public mus::WindowObserver {
       const std::string& name,
       const std::vector<uint8_t>* old_data,
       const std::vector<uint8_t>* new_data) override {
-    if (controller_->user_window_observer() &&
-        name == mus::mojom::WindowManager::kWindowTitle_Property) {
+    if (!controller_->user_window_observer())
+      return;
+    if (name == mus::mojom::WindowManager::kWindowTitle_Property) {
       controller_->user_window_observer()->OnUserWindowTitleChanged(
           window->id(), GetWindowTitle(window));
+    } else if (name == mus::mojom::WindowManager::kWindowAppIcon_Property) {
+      controller_->user_window_observer()->OnUserWindowAppIconChanged(
+          window->id(), new_data ? mojo::Array<uint8_t>::From(*new_data)
+                                 : mojo::Array<uint8_t>());
     }
   }
 
   UserWindowControllerImpl* controller_;
-  DISALLOW_COPY_AND_ASSIGN(WindowTitleObserver);
+  DISALLOW_COPY_AND_ASSIGN(WindowPropertyObserver);
 };
 
 UserWindowControllerImpl::UserWindowControllerImpl()
@@ -87,7 +106,7 @@ UserWindowControllerImpl::~UserWindowControllerImpl() {
 
   user_container->RemoveObserver(this);
   for (auto iter : user_container->children())
-    iter->RemoveObserver(window_title_observer_.get());
+    iter->RemoveObserver(window_property_observer_.get());
 }
 
 void UserWindowControllerImpl::Initialize(
@@ -97,9 +116,9 @@ void UserWindowControllerImpl::Initialize(
   root_controller_ = root_controller;
   GetUserWindowContainer()->AddObserver(this);
   GetUserWindowContainer()->connection()->AddObserver(this);
-  window_title_observer_.reset(new WindowTitleObserver(this));
+  window_property_observer_.reset(new WindowPropertyObserver(this));
   for (auto iter : GetUserWindowContainer()->children())
-    iter->AddObserver(window_title_observer_.get());
+    iter->AddObserver(window_property_observer_.get());
 }
 
 mus::Window* UserWindowControllerImpl::GetUserWindowContainer() const {
@@ -110,11 +129,11 @@ mus::Window* UserWindowControllerImpl::GetUserWindowContainer() const {
 void UserWindowControllerImpl::OnTreeChanging(const TreeChangeParams& params) {
   DCHECK(root_controller_);
   if (params.new_parent == GetUserWindowContainer()) {
-    params.target->AddObserver(window_title_observer_.get());
+    params.target->AddObserver(window_property_observer_.get());
     if (user_window_observer_)
       user_window_observer_->OnUserWindowAdded(GetUserWindow(params.target));
   } else if (params.old_parent == GetUserWindowContainer()) {
-    params.target->RemoveObserver(window_title_observer_.get());
+    params.target->RemoveObserver(window_property_observer_.get());
     if (user_window_observer_)
       user_window_observer_->OnUserWindowRemoved(params.target->id());
   }
diff --git a/mash/wm/user_window_controller_impl.h b/mash/wm/user_window_controller_impl.h
index 3b6f9c4..c974f6f 100644
--- a/mash/wm/user_window_controller_impl.h
+++ b/mash/wm/user_window_controller_impl.h
@@ -17,7 +17,7 @@ namespace mash {
 namespace wm {
 
 class RootWindowController;
-class WindowTitleObserver;
+class WindowPropertyObserver;
 
 class UserWindowControllerImpl : public mojom::UserWindowController,
                                  public mus::WindowObserver,
@@ -49,7 +49,7 @@ class UserWindowControllerImpl : public mojom::UserWindowController,
 
   RootWindowController* root_controller_;
   mojom::UserWindowObserverPtr user_window_observer_;
-  scoped_ptr<WindowTitleObserver> window_title_observer_;
+  scoped_ptr<WindowPropertyObserver> window_property_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(UserWindowControllerImpl);
 };
diff --git a/mash/wm/window_manager.cc b/mash/wm/window_manager.cc
index 5905469f..4ebeb9a 100644
--- a/mash/wm/window_manager.cc
+++ b/mash/wm/window_manager.cc
@@ -153,6 +153,7 @@ bool WindowManager::OnWmSetProperty(
   return name == mus::mojom::WindowManager::kShowState_Property ||
          name == mus::mojom::WindowManager::kPreferredSize_Property ||
          name == mus::mojom::WindowManager::kResizeBehavior_Property ||
+         name == mus::mojom::WindowManager::kWindowAppIcon_Property ||
          name == mus::mojom::WindowManager::kWindowTitle_Property;
 }