Revert "reland: shelf: Add a back button to the shelf."

This reverts commit c8bf13e0.

Reason for revert: It broke compile on a bunch of ChromiumOS bots, e.g. https://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Full

Original change's description:
> reland: shelf: Add a back button to the shelf.
> 
> This is in preparation for removing title bars work. See mocks in the bug and screenshots for more details.
> This approach of adding a back button expands the current app list button to be modal and have two functionalities
> depending on which side is pressed. The alternative (seperate back button) is IMO very difficult to achieve what
> is shown in the mocks (namely the color in between and animation (not in this CL) of said color in between). The
> exact functionality of the back button is not 100% defined yet, this CL just sends a VKEY_BROWSER_BACK event in the
> meantime.
> 
> Screenshots:
> https://screenshot.googleplex.com/ZVNP0aq0cc3
> https://screenshot.googleplex.com/fDcGTuoyZg5
> https://screenshot.googleplex.com/ZFBzk72LLVt
> 
> Test: ash_unittests --gtest_filter="AppListButtonInkDropTest.*"
> Bug: 721940
> Change-Id: I691c9fc15294d48a7a0da88ba78550e013d9b869
> Reviewed-on: https://chromium-review.googlesource.com/572434
> Commit-Queue: Sammie Quon <sammiequon@chromium.org>
> Reviewed-by: Michael Wasserman <msw@chromium.org>
> Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
> Cr-Original-Commit-Position: refs/heads/master@{#487491}
> Reviewed-on: https://chromium-review.googlesource.com/576656
> Cr-Commit-Position: refs/heads/master@{#488025}

TBR=msw@chromium.org,oshima@chromium.org,sammiequon@chromium.org

Change-Id: Ia137671938e7b2110c5cef0bd04fee4ecd46e232
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 721940
Reviewed-on: https://chromium-review.googlesource.com/578611Reviewed-by: Scott Little <sclittle@chromium.org>
Commit-Queue: Scott Little <sclittle@chromium.org>
Cr-Commit-Position: refs/heads/master@{#488032}

ash/resources/vector_icons/BUILD.gn

@@ -88,8 +88,6 @@ aggregate_vector_icons("ash_vector_icons") {
     "palette_tray_icon_magnify.icon",
     "palette_tray_icon_metalayer.1x.icon",
     "palette_tray_icon_metalayer.icon",
-    "shelf_back.1x.icon",
-    "shelf_back.icon",
     "shelf_keyboard.1x.icon",
     "shelf_keyboard.icon",
     "shelf_logout.1x.icon",

ash/resources/vector_icons/shelf_back.1x.icon

-// Copyright 2017 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-CANVAS_DIMENSIONS, 16,
-MOVE_TO, 0, 0,
-R_H_LINE_TO, 16,
-R_V_LINE_TO, 16,
-H_LINE_TO, 0,
-CLOSE,
-NEW_PATH,
-PATH_COLOR_ARGB, 0xFF, 0xFF, 0xFF, 0xFF,
-MOVE_TO, 5.2f, 7,
-H_LINE_TO, 15,
-R_V_LINE_TO, 2,
-H_LINE_TO, 5.2f,
-R_LINE_TO, 4.8f, 4.8f,
-LINE_TO, 8.9f, 15,
-LINE_TO, 2, 8,
-R_LINE_TO, 6.9f, -7,
-LINE_TO, 10, 2.2f,
-LINE_TO, 5.2f, 7,
-CLOSE,
-END

ash/resources/vector_icons/shelf_back.icon

-// Copyright 2017 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-CANVAS_DIMENSIONS, 32,
-MOVE_TO, 0, 0,
-R_H_LINE_TO, 32,
-R_V_LINE_TO, 32,
-H_LINE_TO, 0,
-CLOSE,
-NEW_PATH,
-PATH_COLOR_ARGB, 0xFF, 0xFF, 0xFF, 0xFF,
-MOVE_TO, 8.56f, 17.99f,
-R_LINE_TO, 9.65f, 9.98f,
-LINE_TO, 16.18f, 30,
-LINE_TO, 3, 16.49f,
-LINE_TO, 16.18f, 3,
-R_LINE_TO, 2.03f, 2,
-R_LINE_TO, -9.86f, 9.99f,
-H_LINE_TO, 29,
-R_V_LINE_TO, 3,
-CLOSE,
-END

ash/shelf/app_list_button.h

@@ -40,19 +40,15 @@ class ASH_EXPORT AppListButton : public views::ImageButton,
   // Updates background and schedules a paint.
   void UpdateShelfItemBackground(SkColor color);
 
-  // views::ImageButton:
+  // views::ImageButton overrides:
   void OnGestureEvent(ui::GestureEvent* event) override;
 
-  // Get the center point of the app list button circle used to draw its
-  // background and ink drops.
-  gfx::Point GetAppListButtonCenterPoint() const;
-
-  // Get the center point of the app list button back arrow. Returns an empty
-  // gfx::Point if the back arrow is not shown.
-  gfx::Point GetBackButtonCenterPoint() const;
+  // Get the center point of the app list button used to draw its background and
+  // ink drops.
+  gfx::Point GetCenterPoint() const;
 
  protected:
-  // views::ImageButton:
+  // views::ImageButton overrides:
   bool OnMousePressed(const ui::MouseEvent& event) override;
   void OnMouseReleased(const ui::MouseEvent& event) override;
   void OnMouseCaptureLost() override;
@@ -66,22 +62,13 @@ class ASH_EXPORT AppListButton : public views::ImageButton,
   void PaintButtonContents(gfx::Canvas* canvas) override;
 
  private:
-  // ShellObserver:
+  // ShellObserver overrides:
   void OnAppListVisibilityChanged(bool shown,
                                   aura::Window* root_window) override;
   void OnVoiceInteractionStatusChanged(bool running) override;
 
   void StartVoiceInteractionAnimation();
 
-  // Helper function to determine whether and event at |location| should be
-  // handled by the back button or the app list circle. Returns false if we are
-  // not in maximized mode (there is no back button).
-  bool IsBackEvent(const gfx::Point& location);
-
-  // Generate and send a VKEY_BROWSER_BACK key event when the back button
-  // portion is clicked or tapped.
-  void GenerateAndSendBackEvent(const ui::LocatedEvent& original_event);
-
   // True if the app list is currently showing for this display.
   // This is useful because other IsApplistVisible functions aren't per-display.
   bool is_showing_app_list_;
@@ -100,10 +87,6 @@ class ASH_EXPORT AppListButton : public views::ImageButton,
 
   bool voice_interaction_running_ = false;
 
-  // Flag that gets set each time we receive a mouse or gesture event. It is
-  // then used to render the ink drop in the right location.
-  bool last_event_is_back_event_ = false;
-
   DISALLOW_COPY_AND_ASSIGN(AppListButton);
 };
 

ash/shelf/shelf_view.cc

@@ -28,7 +28,6 @@
 #include "ash/shell_delegate.h"
 #include "ash/shell_port.h"
 #include "ash/strings/grit/ash_strings.h"
-#include "ash/wm/maximize_mode/maximize_mode_controller.h"
 #include "ash/wm/root_window_finder.h"
 #include "base/auto_reset.h"
 #include "base/memory/ptr_util.h"
@@ -756,31 +755,15 @@ void ShelfView::CalculateIdealBounds(gfx::Rect* overflow_bounds) const {
 
   int w = shelf_->PrimaryAxisValue(kShelfButtonSize, width());
   int h = shelf_->PrimaryAxisValue(height(), kShelfButtonSize);
-
-  const bool is_maximize_mode = Shell::Get()->maximize_mode_controller()
-                                    ? Shell::Get()
-                                          ->maximize_mode_controller()
-                                          ->IsMaximizeModeWindowManagerEnabled()
-                                    : false;
-
   for (int i = 0; i < view_model_->view_size(); ++i) {
     if (i < first_visible_index_) {
       view_model_->set_ideal_bounds(i, gfx::Rect(x, y, 0, 0));
       continue;
     }
 
-    int width = w;
-    int height = h;
-    // If this is the app list button and we are in maximize/tablet mode, make
-    // space for the back button (which is part of the app list button).
-    if (i == 0 && is_maximize_mode) {
-      width = shelf_->PrimaryAxisValue(2 * w + kShelfButtonSpacing, w);
-      height = shelf_->PrimaryAxisValue(h, 2 * h + kShelfButtonSpacing);
-    }
-
-    view_model_->set_ideal_bounds(i, gfx::Rect(x, y, width, height));
-    x = shelf_->PrimaryAxisValue(x + width + kShelfButtonSpacing, x);
-    y = shelf_->PrimaryAxisValue(y, y + height + kShelfButtonSpacing);
+    view_model_->set_ideal_bounds(i, gfx::Rect(x, y, w, h));
+    x = shelf_->PrimaryAxisValue(x + w + kShelfButtonSpacing, x);
+    y = shelf_->PrimaryAxisValue(y, y + h + kShelfButtonSpacing);
   }
 
   if (is_overflow_mode()) {

ash/shelf/shelf_view_unittest.cc

@@ -35,7 +35,6 @@
 #include "ash/test_shell_delegate.h"
 #include "ash/wallpaper/wallpaper_controller.h"
 #include "ash/wallpaper/wallpaper_controller_test_api.h"
-#include "ash/wm/maximize_mode/maximize_mode_controller.h"
 #include "base/i18n/rtl.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
@@ -2568,129 +2567,6 @@ TEST_F(ShelfViewInkDropTest, ShelfButtonWithMenuPressRelease) {
 
 namespace {
 
-// Test fixture to run app list button ink drop tests for both mouse and touch
-// events.
-class AppListButtonInkDropTest
-    : public ShelfViewInkDropTest,
-      public testing::WithParamInterface<ui::EventPointerType> {
- public:
-  AppListButtonInkDropTest() : pointer_type_(GetParam()) {}
-
-  ~AppListButtonInkDropTest() override {}
-
-  void MovePointerTo(const gfx::Point& point) {
-    if (pointer_type_ == ui::EventPointerType::POINTER_TYPE_MOUSE)
-      GetEventGenerator().MoveMouseTo(point);
-    else if (pointer_type_ == ui::EventPointerType::POINTER_TYPE_TOUCH)
-      GetEventGenerator().MoveTouch(point);
-  }
-
-  void PressPointer() {
-    if (pointer_type_ == ui::EventPointerType::POINTER_TYPE_MOUSE)
-      GetEventGenerator().PressLeftButton();
-    else if (pointer_type_ == ui::EventPointerType::POINTER_TYPE_TOUCH)
-      GetEventGenerator().PressTouch();
-  }
-
-  void ReleasePointer() {
-    if (pointer_type_ == ui::EventPointerType::POINTER_TYPE_MOUSE)
-      GetEventGenerator().ReleaseLeftButton();
-    else if (pointer_type_ == ui::EventPointerType::POINTER_TYPE_TOUCH)
-      GetEventGenerator().ReleaseTouch();
-  }
-
- private:
-  ui::EventPointerType pointer_type_;
-
-  DISALLOW_COPY_AND_ASSIGN(AppListButtonInkDropTest);
-};
-
-const ui::EventPointerType kPointerTypes[] = {
-    ui::EventPointerType::POINTER_TYPE_MOUSE,
-    ui::EventPointerType::POINTER_TYPE_TOUCH};
-
-}  // namespace
-
-// Tests that clicking/tapping on the app list button in maximized mode (when
-// it has two functionalities), transitions the ink drop state correctly.
-TEST_P(AppListButtonInkDropTest, AppListButtonInMaximizedMode) {
-  // TODO: investigate failure in mash, http://crbug.com/695751.
-  if (Shell::GetAshConfig() == Config::MASH)
-    return;
-
-  InitAppListButtonInkDrop();
-
-  // Verify the app list button bounds change when we enter maximized mode.
-  const gfx::Rect old_bounds = app_list_button_->GetBoundsInScreen();
-  Shell::Get()->maximize_mode_controller()->EnableMaximizeModeWindowManager(
-      true);
-  gfx::Rect new_bounds = app_list_button_->GetBoundsInScreen();
-  EXPECT_EQ(new_bounds.height(), old_bounds.height());
-  EXPECT_GT(new_bounds.width(), old_bounds.width());
-
-  gfx::Point point_on_circle = app_list_button_->GetAppListButtonCenterPoint();
-  views::View::ConvertPointToScreen(app_list_button_, &point_on_circle);
-  gfx::Point point_on_back_button =
-      app_list_button_->GetBackButtonCenterPoint();
-  views::View::ConvertPointToScreen(app_list_button_, &point_on_back_button);
-
-  // Verify the ink drop state transitions as expected when we press and
-  // release on the app list circle part of the app list button. Taps on the
-  // app list circle, which shows the app list, should end up in the activated
-  // state.
-  MovePointerTo(point_on_circle);
-  PressPointer();
-  EXPECT_EQ(views::InkDropState::ACTION_PENDING,
-            app_list_button_ink_drop_->GetTargetInkDropState());
-  EXPECT_THAT(app_list_button_ink_drop_->GetAndResetRequestedStates(),
-              ElementsAre(views::InkDropState::ACTION_PENDING));
-  ReleasePointer();
-
-  // Trigger a mock button notification that the app list was shown.
-  app_list_button_->OnAppListShown();
-  FinishAppListVisibilityChange();
-  EXPECT_EQ(views::InkDropState::ACTIVATED,
-            app_list_button_ink_drop_->GetTargetInkDropState());
-  EXPECT_THAT(app_list_button_ink_drop_->GetAndResetRequestedStates(),
-              ElementsAre(views::InkDropState::ACTIVATED));
-
-  // Trigger a mock button notification that the app list was dismissed.
-  app_list_button_->OnAppListDismissed();
-  FinishAppListVisibilityChange();
-  EXPECT_EQ(views::InkDropState::HIDDEN,
-            app_list_button_ink_drop_->GetTargetInkDropState());
-  EXPECT_THAT(app_list_button_ink_drop_->GetAndResetRequestedStates(),
-              ElementsAre(views::InkDropState::DEACTIVATED));
-
-  // Verify the ink drop state transitions as expected when we tap on the back
-  // button part of the app list button.
-  MovePointerTo(point_on_back_button);
-  PressPointer();
-  EXPECT_EQ(views::InkDropState::ACTION_PENDING,
-            app_list_button_ink_drop_->GetTargetInkDropState());
-  EXPECT_THAT(app_list_button_ink_drop_->GetAndResetRequestedStates(),
-              ElementsAre(views::InkDropState::ACTION_PENDING));
-  ReleasePointer();
-  EXPECT_EQ(views::InkDropState::HIDDEN,
-            app_list_button_ink_drop_->GetTargetInkDropState());
-  EXPECT_THAT(app_list_button_ink_drop_->GetAndResetRequestedStates(),
-              ElementsAre(views::InkDropState::ACTION_TRIGGERED));
-
-  // Verify when we leave maximized mode, the bounds should return to be the
-  // same as they were before we entered maximized mode.
-  Shell::Get()->maximize_mode_controller()->EnableMaximizeModeWindowManager(
-      false);
-  new_bounds = app_list_button_->GetBoundsInScreen();
-  EXPECT_EQ(new_bounds, old_bounds);
-}
-
-INSTANTIATE_TEST_CASE_P(
-    /* prefix intentionally left blank due to only one parameterization */,
-    AppListButtonInkDropTest,
-    ::testing::ValuesIn(kPointerTypes));
-
-namespace {
-
 // An empty menu model for shell context menu just to have a menu.
 class TestShellMenuModel : public ui::SimpleMenuModel,
                            public ui::SimpleMenuModel::Delegate {

ash/shelf/voice_interaction_overlay.cc

@@ -470,7 +470,7 @@ void VoiceInteractionOverlay::StartAnimation(bool show_icon) {
       kRippleCircleStartRadiusDip / kRippleCircleInitRadiusDip;
   gfx::Transform transform;
 
-  const gfx::Point center = host_view_->GetAppListButtonCenterPoint();
+  const gfx::Point center = host_view_->GetCenterPoint();
   transform.Translate(center.x() - kRippleCircleStartRadiusDip,
                       center.y() - kRippleCircleStartRadiusDip);
   transform.Scale(scale_factor, scale_factor);
@@ -568,7 +568,7 @@ void VoiceInteractionOverlay::BurstAnimation() {
   is_bursting_ = true;
   should_hide_animation_ = false;
 
-  gfx::Point center = host_view_->GetAppListButtonCenterPoint();
+  gfx::Point center = host_view_->GetCenterPoint();
   gfx::Transform transform;
 
   // Setup ripple animations.
@@ -646,7 +646,7 @@ void VoiceInteractionOverlay::EndAnimation() {
       kRippleCircleStartRadiusDip / kRippleCircleInitRadiusDip;
   gfx::Transform transform;
 
-  const gfx::Point center = host_view_->GetAppListButtonCenterPoint();
+  const gfx::Point center = host_view_->GetCenterPoint();
   transform.Translate(center.x() - kRippleCircleStartRadiusDip,
                       center.y() - kRippleCircleStartRadiusDip);
   transform.Scale(scale_factor, scale_factor);