[directorytree] Update files-ng 20px computer and shared SVG icons

Replace computer and shared SVG icons with viewBox="0 0 20 20" version
from UX, and optimize them using SVGOMG.

Bug: 992819, 1002393
Change-Id: I3f2d7625cb1d72e42a540e6da93a21bf186a819d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1913779Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#714831}

ui/file_manager/file_manager/foreground/images/volumes/computer.svg

-<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 24 24">
-  <path d="M20 18c1.1 0 1.99-.9 1.99-2L22 6c0-1.1-.9-2-2-2H4c-1.1 0-2 .9-2 2v10c0 1.1.9 2 2 2H0v2h24v-2h-4zM4 6h16v10H4V6z"/>
+<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20">
+  <path d="M2 14V4a1 1 0 011-1h14a1 1 0 011 1v10a1 1 0 01-1 1h2a1 1 0 110 2H1a1 1 0 110-2h2a1 1 0 01-1-1zm14-9H4v8h12V5z"/>
 </svg>

ui/file_manager/file_manager/foreground/images/volumes/shared.svg

-<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 24 24">
-  <path d="M16 11c1.66 0 2.99-1.34 2.99-3S17.66 5 16 5c-1.66 0-3 1.34-3 3s1.34 3 3 3zm-8 0c1.66 0 2.99-1.34 2.99-3S9.66 5 8 5C6.34 5 5 6.34 5 8s1.34 3 3 3zm0 2c-2.33 0-7 1.17-7 3.5V19h14v-2.5c0-2.33-4.67-3.5-7-3.5zm8 0c-.29 0-.62.02-.97.05 1.16.84 1.97 1.97 1.97 3.45V19h6v-2.5c0-2.33-4.67-3.5-7-3.5z"/>
+<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20">
+  <path d="M7.5 11c2.106 0 6.279 1.034 6.492 3.086l.008.164V17H1v-2.75C1 12.089 5.339 11 7.5 11zm5.901.05c2.21.232 5.405 1.247 5.59 3.036l.009.164V17h-3.5v-2.75l-.01-.241c-.127-1.227-.932-2.22-2.089-2.959zM7.5 13c-.927 0-2.292.26-3.317.671-.447.179-.799.373-1.026.554l-.09.076c-.048.045-.063.053-.067.032V15h9v-.666l-.005.01c-.008.004-.026-.01-.062-.043l-.09-.076c-.227-.18-.58-.375-1.026-.554C9.791 13.261 8.427 13 7.5 13zm5-10C14.425 3 16 4.575 16 6.5S14.425 10 12.5 10c-.432 0-.846-.08-1.229-.224a4.978 4.978 0 00.001-6.552A3.458 3.458 0 0112.5 3zm-5 0C9.425 3 11 4.575 11 6.5S9.425 10 7.5 10 4 8.425 4 6.5 5.575 3 7.5 3zm0 2C6.68 5 6 5.68 6 6.5S6.68 8 7.5 8 9 7.32 9 6.5 8.32 5 7.5 5z"/>
 </svg>