[Mac][Material Design] Rework how location bar shadow is drawn.

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 296 matching lines @@
   // lay between cooridnate space lines).
   CGFloat insetSize = 1 - singlePixelLineWidth_ / 2.;
   if (isModeMaterial && showingFirstResponder && !inDarkMode) {
     insetSize++;
   } else if (!isModeMaterial) {
     insetSize = singlePixelLineWidth_ == 0.5 ? 1.5 : 2.0;
   }
 
   // Compute the border's bezier path.
   NSRect pathRect = NSInsetRect(frame, insetSize, insetSize);
-  // In dark mode, make room for a shadow beneath the bottom edge.
-  if (inDarkMode && isModeMaterial) {
-    pathRect.size.height -= singlePixelLineWidth_;
-  }
   NSBezierPath* path =
       [NSBezierPath bezierPathWithRoundedRect:pathRect
                                       xRadius:kCornerRadius
                                       yRadius:kCornerRadius];
   if (isModeMaterial) {
     [path setLineWidth:showingFirstResponder ? singlePixelLineWidth_ * 2
                                              : singlePixelLineWidth_];
   }
 
   // Fill the background.
@@ skipping 28 matching lines @@
       }
       {
         gfx::ScopedNSGraphicsContextSaveGState saveState;
         [[NSColor colorWithCalibratedWhite:71 / 255. alpha:1] set];
         [NSBezierPath clipRect:NSMakeRect(NSMinX(frame), NSMinY(frame),
                                           NSWidth(frame), 3)];
         [path stroke];
       }
 
       // Draw a highlight beneath the top edge, and a shadow beneath the bottom
-      // edge.
+      // edge when on a Retina screen.
       {
         gfx::ScopedNSGraphicsContextSaveGState saveState;
         [NSBezierPath setDefaultLineWidth:singlePixelLineWidth_];
 
         [[NSColor colorWithCalibratedWhite:120 / 255. alpha:1] set];
         NSPoint origin = NSMakePoint(NSMinX(pathRect) + 3,
                                      NSMinY(pathRect) + singlePixelLineWidth_);
         NSPoint destination =
             NSMakePoint(NSMaxX(pathRect) - 3,
                         NSMinY(pathRect) + singlePixelLineWidth_);
         [NSBezierPath strokeLineFromPoint:origin
                                   toPoint:destination];
 
-        origin.y = destination.y = NSMaxY(pathRect) + singlePixelLineWidth_;
-        [[NSColor colorWithCalibratedWhite:69 / 255. alpha:1] set];
-        [NSBezierPath strokeLineFromPoint:origin
-                                  toPoint:destination];
+        if (singlePixelLineWidth_ < 1) {
+          origin.y = destination.y = NSMaxY(pathRect) + singlePixelLineWidth_;
+          [[AutocompleteTextField shadowColor] set];
+          [NSBezierPath strokeLineFromPoint:origin
+                                    toPoint:destination];
+        }
       }
     }
   } else {
     ui::DrawNinePartImage(frame,
                           isPopupMode_ ? kPopupBorderImageIds
                                        : kNormalBorderImageIds,
                           NSCompositeSourceOver,
                           1.0,
                           true);
   }
@@ skipping 367 matching lines @@
 
 - (void)handleFocusEvent:(NSEvent*)event
                   ofView:(AutocompleteTextField*)controlView {
   if ([controlView observer]) {
     const bool controlDown = ([event modifierFlags] & NSControlKeyMask) != 0;
     [controlView observer]->OnSetFocus(controlDown);
   }
 }
 
 @end