omnibox: use dark border stroke in Increase Contrast mode

chrome/browser/ui/cocoa/location_bar/autocomplete_text_field_cell.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 "chrome/browser/ui/cocoa/location_bar/autocomplete_text_field_cell.h"
 
 #include <stddef.h>
 
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
@@ skipping 343 matching lines @@
 
   // Fill the background.
   [[self backgroundColor] set];
   if (isPopupMode_) {
     NSRectFillUsingOperation(NSInsetRect(frame, 1, 1), NSCompositeSourceOver);
   } else {
     [path fill];
   }
 
   // Draw the border.
+  const ui::ThemeProvider* provider = [[controlView window] themeProvider];
+  bool increaseContrast = provider && provider->ShouldIncreaseContrast();
   if (!inDarkMode) {
-    const CGFloat kNormalStrokeGray = 168 / 255.;
-    [[NSColor colorWithCalibratedWhite:kNormalStrokeGray alpha:1] set];
+    if (increaseContrast) {
+      [[NSColor blackColor] set];
+    } else {
+      const CGFloat kNormalStrokeGray = 168 / 255.;
+      [[NSColor colorWithCalibratedWhite:kNormalStrokeGray alpha:1] set];
+    }
   } else {
-    const CGFloat k30PercentAlpha = 0.3;
-    [[NSColor colorWithCalibratedWhite:0 alpha:k30PercentAlpha] set];
+    if (increaseContrast) {
+      [[NSColor whiteColor] set];
+    } else {
+      const CGFloat k30PercentAlpha = 0.3;
+      [[NSColor colorWithCalibratedWhite:0 alpha:k30PercentAlpha] set];
+    }
   }
   [path stroke];
 
   // Draw the interior contents. We do this after drawing the border as some
   // of the interior controls draw over it.
   [self drawInteriorWithFrame:frame inView:controlView];
 
   // Draw the focus ring.
   if (showingFirstResponder) {
     CGFloat alphaComponent = 0.5 / singlePixelLineWidth_;
@@ skipping 348 matching lines @@
 
 @end
 
 @implementation AutocompleteTextFieldCell (TestingAPI)
 
 - (const std::vector<LocationBarDecoration*>&)mouseTrackingDecorations {
   return mouseTrackingDecorations_;
 }
 
 @end