[MD Settings] Implement search in material design passwords.

chrome/browser/resources/settings/settings_page/settings_subpage_search.html

+<link rel="import" href="chrome://resources/cr_elements/cr_search_field/cr_search_field_behavior.html">
+<link rel="import" href="chrome://resources/html/polymer.html">
+<link rel="import" href="chrome://resources/polymer/v1_0/paper-input/paper-input-container.html">
+<link rel="import" href="chrome://resources/polymer/v1_0/paper-input/paper-input.html">
+
+<dom-module id="settings-subpage-search">
+  <template>
+    <style>
+      paper-input-container {
+        width: var(--paper-input-max-width);
+      }
+
+      input[type='search']::-webkit-search-cancel-button {
+        -webkit-appearance: none;
+      }
+
+      #prompt,
+      #searchInput {
+        color: var(--google-grey-500);
+        font-size: 13px;
+        line-height: 36px;
+      }
+
+      #clearSearch {
+        -webkit-margin-end: -8px;
+        -webkit-margin-start: 8px;
+      }
+
+      :root {
+        --paper-icon-button {
+          height: 36px;
+          width: 36px;
+        }
+
+        --paper-input-suffix: {
+          /* Required to align the icon in |clearSearch| vertically. */
+          line-height: 0;
+        }
+      }
+    </style>
+    <paper-input-container no-label-float on-search="onSearchTermSearch">
+      <label id="prompt">[[label]]</label>
+      <input is="iron-input" id="searchInput" type="search"
+          aria-labelledby="prompt" incremental>
+      </input>
+      <paper-icon-button suffix icon="cr:cancel" id="clearSearch"
+          on-tap="onTapClear_" title="[[clearLabel]]"
+          hidden$="[[!hasSearchTerm_(lastValue_)]]">
+      </paper-icon-button>
+    </paper-input-container>
+  </template>
+  <script src="settings_subpage_search.js"></script>
+</dom-module>