Fixed Windows system tray icon.

chrome/browser/background/background_mode_manager.cc

Index: chrome/browser/background/background_mode_manager.cc
diff --git a/chrome/browser/background/background_mode_manager.cc b/chrome/browser/background/background_mode_manager.cc
index 7cd746708b3c3ce691492e25eb8333998d96fe41..f392156ee77a0052224a3464fa075ec0a730f01a 100644
--- a/chrome/browser/background/background_mode_manager.cc
+++ b/chrome/browser/background/background_mode_manager.cc
@@ -49,6 +49,7 @@
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/chromium_strings.h"
 #include "chrome/grit/generated_resources.h"
+#include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/user_metrics.h"
 #include "extensions/browser/extension_system.h"
@@ -61,6 +62,10 @@
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 
+#if defined(OS_WIN)
+#include "chrome/browser/app_icon_win.h"
+#endif
+
 using base::UserMetricsAction;
 using extensions::Extension;
 
@@ -754,6 +759,7 @@ void BackgroundModeManager::UpdateKeepAliveAndTrayIcon() {
       keeping_alive_ = true;
       chrome::IncrementKeepAliveCount();
     }
+
     CreateStatusTrayIcon();
     return;
   }
@@ -856,7 +862,45 @@ void BackgroundModeManager::OnBackgroundClientInstalled(
   DisplayClientInstalledNotification(name);
 }
 
+// Gets the image for the status tray icon, at the correct size for the current
+// platform and display settings.
+gfx::ImageSkia GetStatusTrayIcon() {
+#if defined(OS_WIN)
+  // On Windows, use GetSmallAppIconSize to get the correct image size. The
+  // user's "text size" setting in Windows determines how large the system tray
+  // icon should be.
+  gfx::Size size = GetSmallAppIconSize();
+
+  // This loads all of the icon images, which is a bit wasteful because we're
+  // going to pick one and throw the rest away, but that is the price of using
+  // the ImageFamily abstraction. Note: We could just use the LoadImage function
+  // from the Windows API, but that does a *terrible* job scaling images.
+  // Therefore, we fetch the images and do our own high-quality scaling.
+  scoped_ptr<gfx::ImageFamily> family = GetAppIconImageFamily();
+  DCHECK(family);
+  if (!family)
+    return gfx::ImageSkia();
+
+  return family->CreateExact(size).AsImageSkia();
+#else
+  // On other platforms, just get a static resource image.
+  return *ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
+      IDR_STATUS_TRAY_ICON);
+#endif
+}
+
 void BackgroundModeManager::CreateStatusTrayIcon() {
+  // Creating the status tray icon can take time (as it has to load and
+  // potentially scale the icon resource), so this task should not block
+  // startup time.
+  content::BrowserThread::PostAfterStartupTask(

[Andrew T Wilson (Slow), 2015/11/23 11:28:11]

This seems incorrect, because it's possible that someone may have called
RemoveStatusTrayIcon() while this task was queued (for example, if we are no
longer in background mode because an extension has been uninstalled, etc).

If we can't take the time during startup to scale an icon, can we instead just
use a static resource image immediately, then queue up a task to replace that
image with a scaled one later via StatusIcon::SetImage()?

[Matt Giuca, 2015/11/24 07:07:46]

That's a good point. But we can work around it by having a "pending" Boolean
which is set to true by calling CreateStatusTrayIcon and false by
RemoveStatusTrayIcon, then CreateStatusTrayIconTask checks that the Boolean is
still set to true.
Hmm, the reason I am doing this is because the static resource is extremely ugly
(because Windows scales it to a size that we can't control for). So I think that
will be a weird experience to see an ugly icon, then have it snap to a nice one.
I'd rather not.

+      FROM_HERE, content::BrowserThread::GetMessageLoopProxyForThread(
+                     content::BrowserThread::UI),
+      base::Bind(&BackgroundModeManager::CreateStatusTrayIconTask,
+                 weak_factory_.GetWeakPtr()));
+}
+
+void BackgroundModeManager::CreateStatusTrayIconTask() {
   // Only need status icons on windows/linux. ChromeOS doesn't allow exiting
   // Chrome and Mac can use the dock icon instead.
 
@@ -872,12 +916,8 @@ void BackgroundModeManager::CreateStatusTrayIcon() {
   if (!status_tray_ || status_icon_)
     return;
 
-  gfx::ImageSkia* image_skia = ui::ResourceBundle::GetSharedInstance().
-      GetImageSkiaNamed(IDR_STATUS_TRAY_ICON);
-
   status_icon_ = status_tray_->CreateStatusIcon(
-      StatusTray::BACKGROUND_MODE_ICON,
-      *image_skia,
+      StatusTray::BACKGROUND_MODE_ICON, GetStatusTrayIcon(),
       l10n_util::GetStringUTF16(IDS_PRODUCT_NAME));
   if (!status_icon_)
     return;