mac: Remove IsOSLion().

chrome/browser/ui/cocoa/spinner_view.mm

Index: chrome/browser/ui/cocoa/spinner_view.mm
diff --git a/chrome/browser/ui/cocoa/spinner_view.mm b/chrome/browser/ui/cocoa/spinner_view.mm
index ee52d1956bbb684edaa582a40b281764dbafed32..7eb8e2836e3514928094c867c715281e88ebf777 100644
--- a/chrome/browser/ui/cocoa/spinner_view.mm
+++ b/chrome/browser/ui/cocoa/spinner_view.mm
@@ -178,10 +178,8 @@ NSString* const kRotationAnimationName = @"RotationAnimationName";
   // Make sure |shapeLayer_|'s content scale factor matches the window's
   // backing depth (e.g. it's 2.0 on Retina Macs). Don't worry about adjusting
   // any other layers because |shapeLayer_| is the only one displaying content.
-  if (base::mac::IsOSLionOrLater()) {
-    CGFloat backingScaleFactor = [[self window] backingScaleFactor];
-    [shapeLayer_ setContentsScale:backingScaleFactor];
-  }
+  CGFloat backingScaleFactor = [[self window] backingScaleFactor];
+  [shapeLayer_ setContentsScale:backingScaleFactor];
 
   // Create the first half of the arc animation, where it grows from a short
   // block to its full length.