MacViews: Use Cocoa folder icons in tree views.

chrome/browser/resource_delegate_mac.mm

+// Copyright 2016 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/resource_delegate_mac.h"
+
+#import <Cocoa/Cocoa.h>
+
+#include "ui/resources/grit/ui_resources.h"
+#include "ui/views/resources/grit/views_resources.h"
+
+namespace ui {
+
+namespace {
+
+const int kFolderIconReportedSizeDIP = 16;
+
+// Returns the icon for the given |hfs_type| defined in Cocoa's IconsCore.h, as
+// a gfx::Image of dimensions |width| X |height|.
+gfx::Image ImageForHFSType(int hfs_type, int width, int height) {
+  NSImage* icon = [[NSWorkspace sharedWorkspace]
+      iconForFileType:NSFileTypeForHFSTypeCode(hfs_type)];
+  DCHECK(icon);
+  [icon setSize:NSMakeSize(width, height)];
+  return gfx::Image([icon retain]);
+}
+
+}  // namespace
+
+MacResourceDelegate::MacResourceDelegate() {}
+
+MacResourceDelegate::~MacResourceDelegate() {}
+
+base::FilePath MacResourceDelegate::GetPathForResourcePack(
+    const base::FilePath& pack_path,
+    ui::ScaleFactor scale_factor) {
+  return pack_path;
+};

[tapted, 2016/01/19 00:38:47]

oh and there shouldn't be semicolons after all these methods -- there's a
linting script that picks this up, but it's only run on presubmit in certain
subdirectories of chrome

[karandeepb, 2016/01/20 10:22:37]

Done.

+
+base::FilePath MacResourceDelegate::GetPathForLocalePack(
+    const base::FilePath& pack_path,
+    const std::string& locale) {
+  return pack_path;
+};
+
+gfx::Image MacResourceDelegate::GetImageNamed(int resource_id) {
+  return GetNativeImageNamed(resource_id, ui::ResourceBundle::RTL_DISABLED);
+};
+
+gfx::Image MacResourceDelegate::GetNativeImageNamed(
+    int resource_id,
+    ui::ResourceBundle::ImageRTL rtl) {
+  // Flipped images are not used on Mac.
+  DCHECK_EQ(rtl, ui::ResourceBundle::RTL_DISABLED);
+
+  switch (resource_id) {
+    // On Mac, return the same assets for the _RTL resources. Consistent with,
+    // e.g., Safari.
+    case IDR_FOLDER_OPEN:
+    case IDR_FOLDER_OPEN_RTL:
+      return ImageForHFSType(kOpenFolderIcon, kFolderIconReportedSizeDIP,
+                             kFolderIconReportedSizeDIP);
+    case IDR_FOLDER_CLOSED:
+    case IDR_FOLDER_CLOSED_RTL:
+      return ImageForHFSType(kGenericFolderIcon, kFolderIconReportedSizeDIP,
+                             kFolderIconReportedSizeDIP);
+  }
+  return gfx::Image();
+};
+
+base::RefCountedStaticMemory* MacResourceDelegate::LoadDataResourceBytes(
+    int resource_id,
+    ui::ScaleFactor scale_factor) {
+  return nullptr;
+};
+
+bool MacResourceDelegate::GetRawDataResource(int resource_id,
+                                             ui::ScaleFactor scale_factor,
+                                             base::StringPiece* value) {
+  return false;
+};
+
+bool MacResourceDelegate::GetLocalizedString(int message_id,
+                                             base::string16* value) {
+  return false;
+};
+
+scoped_ptr<gfx::Font> MacResourceDelegate::GetFont(
+    ui::ResourceBundle::FontStyle style) {
+  return scoped_ptr<gfx::Font>();

[tapted, 2016/01/19 00:36:52]

I think `return nullptr` should work now that we have C++11

[karandeepb, 2016/01/20 10:22:37]

Done.

+};
+
+}  // namespace ui