Add a highlighted version of the Physical Web icon

In preparation for making the icon in Physical Web omnibox suggestions
tappable, add a highlighted version of the icon. This version will be
shown when the icon is tapped.

BUG=630769

Review-Url: https://codereview.chromium.org/2578313002
Cr-Commit-Position: refs/heads/master@{#439152}

ios/chrome/app/theme/ios_theme_resources.grd

@@ -58,6 +58,7 @@
       <structure type="chrome_scaled_image" name="IDR_IOS_OMNIBOX_KEYBOARD_VIEW_APPEND_INCOGNITO_HIGHLIGHTED" file="omnibox/append_incognito_highlighted_ios.png" />
       <structure type="chrome_scaled_image" name="IDR_IOS_OMNIBOX_OFFLINE" file="omnibox_offline.png" />
       <structure type="chrome_scaled_image" name="IDR_IOS_OMNIBOX_PHYSICAL_WEB" file="omnibox/physical_web_ios.png" />
+      <structure type="chrome_scaled_image" name="IDR_IOS_OMNIBOX_PHYSICAL_WEB_HIGHLIGHTED" file="omnibox/physical_web_highlighted_ios.png" />
       <structure type="chrome_scaled_image" name="IDR_IOS_OMNIBOX_SEARCH" file="omnibox_search.png" />
       <structure type="chrome_scaled_image" name="IDR_IOS_OMNIBOX_SEARCH_INCOGNITO" file="omnibox_search_incognito.png" />
       <structure type="chrome_scaled_image" name="IDR_IOS_OMNIBOX_STAR" file="omnibox_star.png" />