Set bookmarks bar text color to #646464 in MD mode

chrome/browser/themes/theme_properties.h

 // Copyright (c) 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_THEMES_THEME_PROPERTIES_H_
 #define CHROME_BROWSER_THEMES_THEME_PROPERTIES_H_
 
 #include <set>
 #include <string>
 
@@ skipping 89 matching lines @@
     COLOR_TOOLBAR_TOP_SEPARATOR,
     COLOR_TOOLBAR_TOP_SEPARATOR_INACTIVE,
 
     // Colors of vertical separators, such as on the bookmark bar or on the DL
     // shelf.
     COLOR_TOOLBAR_VERTICAL_SEPARATOR,
 
     // The color of a background tab, as well as the new tab button.
     COLOR_BACKGROUND_TAB,
 
+    // The color of the "instructions text" in an empty bookmarks bar

[Evan Stade, 2016/06/17 20:23:37]

nit: final punctuation

+    COLOR_BOOKMARK_BAR_INSTRUCTIONS_TEXT,
+
     // Colors used for the detached (NTP) bookmark bar.
     COLOR_DETACHED_BOOKMARK_BAR_BACKGROUND,
     COLOR_DETACHED_BOOKMARK_BAR_SEPARATOR,
 
     // The throbber colors for tabs or anything on a toolbar (currently, only
     // the download shelf). If you're adding a throbber elsewhere, such as in
     // a dialog or bubble, you likely want
     // NativeTheme::kColorId_ThrobberSpinningColor.
     COLOR_TAB_THROBBER_SPINNING,
     COLOR_TAB_THROBBER_WAITING,
@@ skipping 60 matching lines @@
 
   // Returns the default color for the given color |id| COLOR_* enum value.
   // Returns gfx::kPlaceholderColor if |id| is invalid.
   static SkColor GetDefaultColor(int id, bool otr);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(ThemeProperties);
 };
 
 #endif  // CHROME_BROWSER_THEMES_THEME_PROPERTIES_H_