base::mac::IsOSSierra() -> base::mac::IsOS10_12(), etc.

ui/base/cocoa/base_view.mm

Index: ui/base/cocoa/base_view.mm
diff --git a/ui/base/cocoa/base_view.mm b/ui/base/cocoa/base_view.mm
index ef3eb87f7917d20ce91181ac7f411efb87a9ecb0..47ccca96ad6dd866b986183dbbec4db376f85be6 100644
--- a/ui/base/cocoa/base_view.mm
+++ b/ui/base/cocoa/base_view.mm
@@ -61,7 +61,7 @@ NSString* kSelectionDirection = @"Chromium.kSelectionDirection";
   // Work around it by reinstalling the tracking area after window resize.
   // This AppKit bug is fixed on Yosemite, so we only apply this workaround on
   // 10.9.
-  if (base::mac::IsOSMavericks()) {
+  if (base::mac::IsOS10_9()) {
     [self disableTracking];
     [self enableTracking];
   }