[MD History] Focus the search bar on load.

ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar_search_field.html

Index: ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar_search_field.html
diff --git a/ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar_search_field.html b/ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar_search_field.html
index 8bc7d9db044e96e01bab3dcfe86b4fe15f57fe66..49d3981591badf01ec0b816e535143f81df15cad 100644
--- a/ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar_search_field.html
+++ b/ui/webui/resources/cr_elements/cr_toolbar/cr_toolbar_search_field.html
@@ -90,7 +90,7 @@
       }
 
       :host(:not([narrow]):not([showing-search])) #icon,
-      :host(:not([narrow]):not([showing-search])) #prompt {
+      :host(:not([narrow])) #prompt {
         opacity: 0.6;
       }
 
@@ -128,7 +128,9 @@
     </paper-icon-button>
     <paper-input-container id="searchTerm" on-search="onSearchTermSearch"
         on-keydown="onSearchTermKeydown" no-label-float>
-      <label id="prompt" for="searchInput">[[label]]</label>
+      <label id="prompt" for="searchInput" hidden$="[[hasSearchText_]]">

[tsergeant, 2016/08/15 03:28:33]

I don't think you want to use hidden here. paper-input-container will hide the
label itself anyway, and it's important to keep the label around for screen
readers to find.

[calamity, 2016/08/15 07:40:28]

Removed.

+        [[label]]
+      </label>
       <input is="iron-input" id="searchInput" type="search"
           on-blur="onInputBlur_" incremental></input>
     </paper-input-container>