Added the Material Design ink drop ripple effect to the navigation buttons in the browser toolbar.

chrome/browser/ui/views/toolbar/toolbar_button.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/ui/views/toolbar/toolbar_button.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
 #include "chrome/browser/themes/theme_properties.h"
 #include "chrome/browser/ui/views/location_bar/location_bar_view.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/models/menu_model.h"
 #include "ui/base/resource/material_design/material_design_controller.h"
 #include "ui/base/theme_provider.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/screen.h"
 #include "ui/strings/grit/ui_strings.h"
+#include "ui/views/animation/ink_drop_animation_controller.h"
 #include "ui/views/controls/button/label_button_border.h"
 #include "ui/views/controls/menu/menu_item_view.h"
 #include "ui/views/controls/menu/menu_model_adapter.h"
 #include "ui/views/controls/menu/menu_runner.h"
 #include "ui/views/widget/widget.h"
 
 ToolbarButton::ToolbarButton(views::ButtonListener* listener,
                              ui::MenuModel* model)
     : views::LabelButton(listener, base::string16()),
       model_(model),
       menu_showing_(false),
       y_position_on_lbuttondown_(0),
       show_menu_factory_(this) {
+#if defined(OS_CHROMEOS)

[Peter Kasting, 2015/07/20 19:15:59]

Can you at least add a comment here about why we're only doing this on CrOS?  If
there is a plan to revisit this decision in the future a TODO for that might be
warranted as well.

[bruthig, 2015/07/21 13:41:03]

Done.

+  if (ui::MaterialDesignController::IsModeMaterial()) {
+    ink_drop_animation_controller_.reset(
+        new views::InkDropAnimationController(this));
+    layer()->SetFillsBoundsOpaquely(false);
+    image()->SetPaintToLayer(true);
+    image()->SetFillsBoundsOpaquely(false);
+  }
+#endif  // defined(OS_CHROMEOS)
+
   set_context_menu_controller(this);
 }
 
 ToolbarButton::~ToolbarButton() {
 }
 
 void ToolbarButton::Init() {
   SetFocusable(false);
   SetAccessibilityFocusable(true);
   image()->EnableCanvasFlippingForRTLUI(true);
@@ skipping 97 matching lines @@
   state->role = ui::AX_ROLE_BUTTON_DROP_DOWN;
   state->default_action = l10n_util::GetStringUTF16(IDS_APP_ACCACTION_PRESS);
   state->AddStateFlag(ui::AX_STATE_HASPOPUP);
 }
 
 scoped_ptr<views::LabelButtonBorder>
 ToolbarButton::CreateDefaultBorder() const {
   scoped_ptr<views::LabelButtonBorder> border =
       LabelButton::CreateDefaultBorder();
 
+  if (ui::MaterialDesignController::IsModeMaterial()) {
+    // The material design spec does not include a visual effect for the
+    // STATE_HOVERED button state so we have to remove the default one added by
+    // LabelButton::CreateDefaultBorder().
+    border->SetPainter(true, Button::STATE_HOVERED, nullptr);
+    border->SetPainter(false, Button::STATE_HOVERED, nullptr);
+
+#if defined(OS_CHROMEOS)
+    // The default STATE_PRESSED painters need to be removed so that they do not
+    // conflict with the ink drop ripple effect.
+    border->SetPainter(true, Button::STATE_PRESSED, nullptr);
+    border->SetPainter(false, Button::STATE_PRESSED, nullptr);
+#endif  // defined(OS_CHROMEOS)
+  }
+
   ui::ThemeProvider* provider = GetThemeProvider();
   if (provider && provider->UsingSystemTheme()) {
     // Theme provided insets.
     int inset = provider->GetDisplayProperty(
         ThemeProperties::PROPERTY_TOOLBAR_BUTTON_BORDER_INSET);
     border->set_insets(gfx::Insets(inset, inset, inset, inset));
   }
 
   return border.Pass();
 }
@@ skipping 100 matching lines @@
   SetMouseHandler(NULL);
 
   // Set the state back to normal after the drop down menu is closed.
   if (state_ != STATE_DISABLED)
     SetState(STATE_NORMAL);
 }
 
 const char* ToolbarButton::GetClassName() const {
   return "ToolbarButton";
 }