[Mac][Material Design] Update Omnibox dropdown on Mac to MD

chrome/browser/ui/cocoa/omnibox/omnibox_popup_matrix.h

 // Copyright 2013 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.
 
 #ifndef CHROME_BROWSER_UI_COCOA_OMNIBOX_OMNIBOX_POPUP_MATRIX_H_
 #define CHROME_BROWSER_UI_COCOA_OMNIBOX_OMNIBOX_POPUP_MATRIX_H_
 
 #import <Cocoa/Cocoa.h>
 #include <stddef.h>
 
@@ skipping 50 matching lines @@
 @interface OmniboxPopupMatrix : NSTableView {
   base::scoped_nsobject<OmniboxPopupTableController> matrixController_;
   OmniboxPopupMatrixObserver* observer_;  // weak
   ui::ScopedCrTrackingArea trackingArea_;
   NSAttributedString* separator_;
 
   // The width of widest match contents in a set of infinite suggestions.
   CGFloat maxMatchContentsWidth_;
 
   CGFloat answerLineHeight_;
+
+  // Left margin padding for the content (i.e. icon and text) in a cell.
+  CGFloat contentLeftPadding_;
+
+  // true if the OmniboxPopupMatrix should use the dark theme style.
+  BOOL hasDarkTheme_;
 }
 
 @property(retain, nonatomic) NSAttributedString* separator;
 @property(nonatomic) CGFloat maxMatchContentsWidth;
 @property(nonatomic) CGFloat answerLineHeight;
+@property(nonatomic) CGFloat contentLeftPadding;
+@property(readonly, nonatomic) BOOL hasDarkTheme;
 
 // Create a zero-size matrix.
-- (instancetype)initWithObserver:(OmniboxPopupMatrixObserver*)observer;
+- (instancetype)initWithObserver:(OmniboxPopupMatrixObserver*)observer
+                    forDarkTheme:(BOOL)isDarkTheme;
 
 // Sets the observer.
 - (void)setObserver:(OmniboxPopupMatrixObserver*)observer;
 
 // Return the currently highlighted row.  Returns -1 if no row is highlighted.
 - (NSInteger)highlightedRow;
 
 // Move the selection to |rowIndex|.
 - (void)selectRowIndex:(NSInteger)rowIndex;
 
 // Setup the NSTableView data source.
 - (void)setController:(OmniboxPopupTableController*)controller;
 
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_OMNIBOX_OMNIBOX_POPUP_MATRIX_H_