Set minimal width for the username in the password bubble on Mac.

chrome/browser/ui/cocoa/passwords/passwords_bubble_utils.mm

 // Copyright 2015 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/passwords/passwords_bubble_utils.h"
 
 #include "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #include "chrome/browser/ui/chrome_style.h"
 #include "skia/ext/skia_utils_mac.h"
@@ skipping 55 matching lines @@
   [textField setDrawsBackground:NO];
   [textField setBezeled:NO];
   [textField setFont:LabelFont()];
   [[textField cell] setLineBreakMode:NSLineBreakByTruncatingTail];
   [textField sizeToFit];
 }
 
 std::pair<CGFloat, CGFloat> GetResizedColumns(
     CGFloat maxWidth,
     std::pair<CGFloat, CGFloat> columnsWidth) {
+  DCHECK_GE(maxWidth, kItemLabelSpacing + kMinUsernameSize);
   // Free space can be negative.
   CGFloat freeSpace =
       maxWidth - (columnsWidth.first + columnsWidth.second + kItemLabelSpacing);
   if (freeSpace >= 0) {
     return std::make_pair(columnsWidth.first + freeSpace / 2,
                           columnsWidth.second + freeSpace / 2);
   }
   // Make sure that the sizes are nonnegative.
   CGFloat firstColumnPercent =
       columnsWidth.first / (columnsWidth.first + columnsWidth.second);
+  CGFloat firstColumnSize = std::max(
+      kMinUsernameSize, columnsWidth.first + freeSpace * firstColumnPercent);
   return std::make_pair(
-      columnsWidth.first + freeSpace * firstColumnPercent,
-      columnsWidth.second + freeSpace * (1 - firstColumnPercent));
+      firstColumnSize,
+      maxWidth - kItemLabelSpacing - firstColumnSize);
 }
 
 NSSecureTextField* PasswordLabel(const base::string16& text) {
   base::scoped_nsobject<NSSecureTextField> textField(
       [[NSSecureTextField alloc] initWithFrame:NSZeroRect]);
   InitLabel(textField, text);
   return textField.autorelease();
 }
 
 NSButton* DialogButton(NSString* title) {
@@ skipping 45 matching lines @@
                                  gfx::Range range,
                                  id<NSTextViewDelegate> delegate) {
   return LabelWithLink(
       text, color,
       ResourceBundle::GetSharedInstance()
           .GetFontList(ResourceBundle::SmallFont)
           .GetPrimaryFont()
           .GetNativeFont(),
       range, delegate);
 }