[NTP] Update color of monochrome Chrome logo

Bug: 859375
Cq-Include-Trybots: luci.chromium.try:closure_compilation
Change-Id: I17777cde0b1ef1e2a3106453ce54c1cabe7a7382
Reviewed-on: https://chromium-review.googlesource.com/1122854Reviewed-by: Marc Treib <treib@chromium.org>
Commit-Queue: Kyle Milka <kmilka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#571920}

chrome/browser/resources/local_ntp/chrome.svg

@@ -3,6 +3,6 @@
     <path id="chrome_16dp-a" d="M8,5.3 L13.34,5.3 C12.38,3.32 10.34,2 8,2 C6.14,2 4.46,2.84 3.38,4.16 L5.36,7.58 C5.54,6.32 6.68,5.3 8,5.3 L8,5.3 Z M8,10.7 C6.98,10.7 6.14,10.16 5.66,9.32 L2.96,4.7 C2.36,5.66 2,6.8 2,8 C2,11 4.16,13.46 7.04,13.94 L9.02,10.52 C8.66,10.64 8.36,10.7 8,10.7 L8,10.7 Z M10.7,8 C10.7,7.16 10.28,6.38 9.68,5.9 L13.64,5.9 C13.88,6.56 14,7.28 14,8 C14,11.3 11.3,14 8,14 L7.64,14 L10.34,9.32 C10.58,8.96 10.7,8.48 10.7,8 Z M8,10.1 C6.84020203,10.1 5.9,9.15979797 5.9,8 C5.9,6.84020203 6.84020203,5.9 8,5.9 C9.15979797,5.9 10.1,6.84020203 10.1,8 C10.1,9.15979797 9.15979797,10.1 8,10.1 Z"/>
   </defs>
   <g fill="none" fill-rule="evenodd">
-    <use fill="#000" xlink:href="#chrome_16dp-a"/>
+    <use fill="#5F6368" xlink:href="#chrome_16dp-a"/>
   </g>
 </svg>