Load the resources for max scale factor first.
- made SCALE_FACTOR_NONE != SCALE_FACTOR_100P
- updated a few places that used SCALE_FACTOR_NONE to load
  100P images
- Don't include 200P to supported scale factor unless
  we have 200P assets (on chromeos)

BUG=156569
TEST=covered by test.

Review URL: https://chromiumcodereview.appspot.com/11301007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@167622 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/ash/shell/window_watcher.cc b/ash/shell/window_watcher.cc
index 97fee7d7..157a598 100644
--- a/ash/shell/window_watcher.cc
+++ b/ash/shell/window_watcher.cc
@@ -91,7 +91,7 @@
                         image_count == 2 ? 255 : 0);
   image_count = (image_count + 1) % 3;
   item.image = gfx::ImageSkia(gfx::ImageSkiaRep(icon_bitmap,
-                                                ui::SCALE_FACTOR_NONE));
+                                                ui::SCALE_FACTOR_100P));
 
   model->Add(item);
 }