Round up button's dimensions so width and height are always pixel-aligned..

chrome/browser/ui/cocoa/website_settings/split_block_button.mm

 // Copyright 2014 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.
 
 #import "chrome/browser/ui/cocoa/website_settings/split_block_button.h"
 
 #include <cmath>
 
 #include "base/logging.h"
 #include "base/mac/scoped_nsobject.h"
@@ skipping 244 matching lines @@
     location = kInsideLeftCell;
   else if ([self mouse:mousePoint inRect:[self rightCellRect]])
     location = kInsideRightCell;
   return location;
 }
 
 - (void)sizeToFit {
   NSSize leftSize = [leftCell_ cellSize];
   NSSize rightSize = [rightCell_ cellSize];
   NSSize size = NSMakeSize(
-      std::max(leftSize.width + rightSize.width,
-               constrained_window_button::kButtonMinWidth),
-      std::max(leftSize.height, rightSize.height));
+      std::ceil(std::max(leftSize.width + rightSize.width,
+                         constrained_window_button::kButtonMinWidth)),
+      std::ceil(std::max(leftSize.height, rightSize.height)));
   [self setFrameSize:size];
 }
 
 - (NSRect)leftCellRect {
   return [leftCell_ rect];
 }
 
 - (NSRect)rightCellRect {
   NSRect leftFrame, rightFrame;
   NSDivideRect([self bounds], &leftFrame, &rightFrame,
@@ skipping 53 matching lines @@
   [super drawBorderAndBackgroundWithFrame:NSOffsetRect(frame, -4, 0)
                                    inView:controlView];
 }
 
 - (NSRect)rect {
   NSSize size = [self cellSize];
   return NSMakeRect(0, 0, std::ceil(size.width), std::ceil(size.height));
 }
 
 @end