update wear icons on preview page

Change-Id: I17fc5a7d1ba637ea0eb557eae50aea76667e2430

docs/html/preview/index.html

@@ -148,7 +148,7 @@ with a user experience that's designed specifically for wearables.
     <div class="landing-body">
       <div class="landing-breakout cols">
         <div class="col-4">
-          <img src="/preview/images/wear-data.png" alt="">
+          <img src="/preview/images/notifications.png" alt="">
           <p>Synced Notifications</p>
           <p class="landing-small">
             Notifications on handhelds can automatically sync to wearables, so design them
@@ -156,7 +156,7 @@ with a user experience that's designed specifically for wearables.
           </p>
         </div>
         <div class="col-4">
-          <img src="/preview/images/wear-apps.png" alt="">
+          <img src="/preview/images/apps.png" alt="">
           <p>Wearable Apps</p>
           <p class="landing-small">
             Create custom experiences with activities, services, sensors, and much
@@ -164,7 +164,7 @@ with a user experience that's designed specifically for wearables.
           </p>
         </div>
         <div class="col-4">
-          <img src="/preview/images/wear-data.png" alt="">
+          <img src="/preview/images/send-data.png" alt="">
           <p>Send Data</p>
           <p class="landing-small">
             Send data and actions between handhelds and wearables with
@@ -172,7 +172,7 @@ with a user experience that's designed specifically for wearables.
           </p>
         </div>
         <div class="col-4">
-          <img src="/preview/images/wear-voice.png" alt="">
+          <img src="/preview/images/voice.png" alt="">
           <p>Voice Actions</p>
           <p class="landing-small">
             Register your app to handle voice actions, like "Ok Google, take a&nbsp;note,"