Implement i18n

Bug: 1099917
Change-Id: I14d98855e3389320ce10a94f161cb94d283c318f
Reviewed-on: https://chrome-internal-review.googlesource.com/c/chrome/browser/resources/tab_search/+/3280945Reviewed-by: Tom Lukaszewicz <tluk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#819605}

chrome/browser/resources/tab_search_merge/app.html

@@ -54,8 +54,8 @@
     </defs>
   </svg>
 </iron-iconset-svg>
-<tab-search-search-field id="searchField" autofocus clear-label="Clear search"
-    label="Search tabs [[getKeyboardShortcut_()]]" on-focus="onSearchFocus_"
+<tab-search-search-field id="searchField" autofocus clear-label="$i18n{clearSearch}"
+    label="$i18n{searchTabs} [[getKeyboardShortcut_()]]" on-focus="onSearchFocus_"
     on-keydown="onSearchKeyDown_" on-search-changed="onSearchChanged_">
 </tab-search-search-field>
 <div id="tabs">
@@ -71,10 +71,10 @@
   </iron-selector>
 </div>
 <div id="no-results" hidden="[[filteredOpenTabs_.length]]">
-  No results found
+  $i18n{noResultsFound}
 </div>
 <button id="feedback-footer" class="mwb-list-item" on-click="onFeedbackClick_"
     on-focus="onFeedbackFocus_">
   <iron-icon id="feedback-icon" icon="ts:feedback"></iron-icon>
-  <div id="feedback-text">Submit feedback</div>
+  <div id="feedback-text">$i18n{submitFeedback}</div>
 </button>

chrome/browser/resources/tab_search_merge/tab_search_item.html

@@ -64,6 +64,6 @@
 </div>
 <div class="button-container">
   <cr-icon-button id="closeButton" aria-labelledby="label"
-      iron-icon="cr:close" on-click="onItemClose_" title="$i18n{close}">
+      iron-icon="cr:close" on-click="onItemClose_" title="$i18n{closeTab}">
   </cr-icon-button>
 </div>