aura: Make the Linux version of IconLoader not require GTK+.

chrome/browser/icon_loader_gtk.cc

-// Copyright (c) 2011 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/icon_loader.h"
-
-#include <gdk-pixbuf/gdk-pixbuf.h>
-#include <gio/gio.h>
-#include <gtk/gtk.h>
-
-#include "base/file_util.h"
-#include "base/logging.h"
-#include "base/message_loop.h"
-#include "base/mime_util.h"
-#include "base/threading/thread.h"
-#include "base/string_util.h"
-
-static int SizeToInt(IconLoader::IconSize size) {
-  int pixels = 0;
-  switch (size) {
-    case IconLoader::SMALL:
-      pixels = 16;
-      break;
-    case IconLoader::NORMAL:
-      pixels = 32;
-      break;
-    case IconLoader::LARGE:
-      pixels = 48;
-      break;
-    default:
-      NOTREACHED();
-  }
-  return pixels;
-}
-
-void IconLoader::ReadIcon() {
-  filename_ = mime_util::GetMimeIcon(group_, SizeToInt(icon_size_));
-  file_util::ReadFileToString(filename_, &icon_data_);
-  target_message_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(this, &IconLoader::ParseIcon));
-}
-
-void IconLoader::ParseIcon() {
-  int size = SizeToInt(icon_size_);
-
-  // It would be more convenient to use gdk_pixbuf_new_from_stream_at_scale
-  // but that is only available after 2.14.
-  GdkPixbufLoader* loader = gdk_pixbuf_loader_new();
-  gdk_pixbuf_loader_set_size(loader, size, size);
-  gdk_pixbuf_loader_write(loader,
-                          reinterpret_cast<const guchar*>(icon_data_.data()),
-                          icon_data_.length(), NULL);
-  gdk_pixbuf_loader_close(loader, NULL);
-  // At this point, the pixbuf is owned by the loader.
-  GdkPixbuf* pixbuf = gdk_pixbuf_loader_get_pixbuf(loader);
-
-  if (pixbuf) {
-    DCHECK_EQ(size, gdk_pixbuf_get_width(pixbuf));
-    DCHECK_EQ(size, gdk_pixbuf_get_height(pixbuf));
-    // Takes ownership of |pixbuf|.
-    g_object_ref(pixbuf);
-    image_.reset(new gfx::Image(pixbuf));
-  } else {
-    LOG(WARNING) << "Unsupported file type or load error: " <<
-                    filename_.value();
-  }
-
-  g_object_unref(loader);
-
-  NotifyDelegate();
-}