[Mac] Refactor the fullscreen menubar

base/mac/mac_util.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/mac/mac_util.h"
 
 #import <Cocoa/Cocoa.h>
 #import <IOKit/IOKitLib.h>
+
+#include <cmath>
 #include <errno.h>
 #include <stddef.h>
 #include <string.h>
 #include <sys/utsname.h>
 #include <sys/xattr.h>
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/mac/bundle_locations.h"
 #include "base/mac/foundation_util.h"
@@ skipping 147 matching lines @@
       DLOG(WARNING) <<
           "Couldn't get the main display's color space, using generic";
     } else {
       DLOG(ERROR) << "Couldn't get any color space";
     }
   }
 
   return g_system_color_space;
 }
 
+bool IsCGFloatEqual(CGFloat a, CGFloat b) {
+  return std::fabs(a - b) <= std::numeric_limits<CGFloat>::epsilon();
+}
+
 // Add a request for full screen mode.  Must be called on the main thread.
 void RequestFullScreen(FullScreenMode mode) {
   DCHECK_LT(mode, kNumFullScreenModes);
   if (mode >= kNumFullScreenModes)
     return;
 
   DCHECK_GE(g_full_screen_requests[mode], 0);
   if (mode < 0)
     return;
 
@@ skipping 289 matching lines @@
           StringPiece(begin + comma_loc + 1, ident.end()), &minor_tmp))
     return false;
   *type = ident.substr(0, number_loc);
   *major = major_tmp;
   *minor = minor_tmp;
   return true;
 }
 
 }  // namespace mac
 }  // namespace base