Settings WebUI: Add back justify-content property for some cr-inputs

<cr-input> had a mixin of --cr-input-row-container that was incorrectly
defaulting the value of the `justify-content` property to normal. When
the mixin was removed, <cr-input>s that relied on that value broke.

Bug: 978337
Change-Id: I37aaf6e260f901714cd6b4068a2f785bb19d2179
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1676745Reviewed-by: Hector Carmona <hcarmona@chromium.org>
Commit-Queue: John Lee <johntlee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#672238}

chrome/browser/resources/settings/appearance_page/home_url_input.html

@@ -20,6 +20,10 @@
         width: 100%;
         --cr-input-width: 50%;
       }
+
+      cr-input::part(row-container) {
+        justify-content: normal;
+      }
     </style>
     <!-- Max length of 100 KB to prevent browser from freezing. -->
     <cr-input id="input" value="{{value}}" error-message="$i18n{notValid}"

chrome/browser/resources/settings/languages_page/edit_dictionary_page.html

@@ -25,6 +25,10 @@
         --cr-input-width: var(--settings-input-max-width);
       }
 
+      #newWord::part(row-container) {
+        justify-content: normal;
+      }
+
       iron-list .word {
         flex: 1;
       }