Prevent infobar buttons title color from changing when disabled

ios/chrome/browser/ui/infobars/infobar_view.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.
 
 #import "ios/chrome/browser/ui/infobars/infobar_view.h"
 
 #import <CoreGraphics/CoreGraphics.h>
 #import <QuartzCore/QuartzCore.h>
 
 #include "base/format_macros.h"
@@ skipping 858 matching lines @@
                        tag:(NSInteger)tag
                     target:(id)target
                     action:(SEL)action {
   base::scoped_nsobject<MDCFlatButton> button([[MDCFlatButton alloc] init]);
   button.get().inkColor = [[palette tint300] colorWithAlphaComponent:0.5f];
   [button setBackgroundColor:[palette tint500] forState:UIControlStateNormal];
   [button setBackgroundColor:[UIColor colorWithWhite:0.8f alpha:1.0f]
                     forState:UIControlStateDisabled];
   if (palette)
     button.get().hasOpaqueBackground = YES;
-  if (customTitleColor)
+  if (customTitleColor) {
+    button.get().tintAdjustmentMode = UIViewTintAdjustmentModeNormal;
     button.get().customTitleColor = customTitleColor;
+  }
   button.get().titleLabel.adjustsFontSizeToFitWidth = YES;
   button.get().titleLabel.minimumScaleFactor = 0.6f;
   [button setTitle:message forState:UIControlStateNormal];
   [button setTag:tag];
   [button addTarget:target
                 action:action
       forControlEvents:UIControlEventTouchUpInside];
   // Without the call to layoutIfNeeded, |button| returns an incorrect
   // titleLabel the first time it is accessed in |narrowestWidthOfButton|.
   [button layoutIfNeeded];
@@ skipping 52 matching lines @@
 
 - (CGFloat)buttonMargin {
   return kButtonMargin;
 }
 
 - (const std::vector<std::pair<NSUInteger, NSRange>>&)linkRanges {
   return linkRanges_;
 }
 
 @end