Mac: Remove some remaining 10.6 logic for absent overlay scrollbar APIs

third_party/WebKit/Source/platform/scroll/ScrollbarThemeMac.mm

Index: third_party/WebKit/Source/platform/scroll/ScrollbarThemeMac.mm
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollbarThemeMac.mm b/third_party/WebKit/Source/platform/scroll/ScrollbarThemeMac.mm
index b20efe35c59a79411a3581de7024857a82ec91ab..898f40d5f1155e0eefcb0916b2598c5c0c26d82e 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollbarThemeMac.mm
+++ b/third_party/WebKit/Source/platform/scroll/ScrollbarThemeMac.mm
@@ -222,7 +222,7 @@ void ScrollbarThemeMac::preferencesChanged(float initialButtonDelay, float autos
     }
     if (sendScrollerStyleNotification) {
         [[NSNotificationCenter defaultCenter]
-            postNotificationName:@"NSPreferredScrollerStyleDidChangeNotification"
+            postNotificationName:NSPreferredScrollerStyleDidChangeNotification

[tapted, 2016/04/05 09:06:02]

nothing in blink seems to listen for this - maybe it's safe to just delete..

[Avi (use Gerrit), 2016/04/05 11:26:32]

delete away.

[Nico, 2016/04/05 12:30:30]

Does chrome do the right thing if you change the preferred scroller style in
sysprefs? (it used to, maybe someone broke that?)

[tapted, 2016/04/05 12:35:17]

Yup - the listener is at content/browser/theme_helper_mac.mm . That feeds
through a change from the browser process into blink, ending up in this method.
Currently, this method then re-broadcasts it, but nothing in blink's code is
subscribing to it.

[tapted, 2016/04/05 12:53:13]

Done.

                           object:nil
                         userInfo:@{ @"NSScrollerStyle" : @(gPreferredScrollerStyle) }];
     }