Doc change: Updates to preview and distribute.

Change-Id: I097213ce68d50d10b23840f2ad61f26279293948
diff --git a/docs/html/preview/samples.jd b/docs/html/preview/samples.jd
index 7e98188..29b9e2a 100644
--- a/docs/html/preview/samples.jd
+++ b/docs/html/preview/samples.jd
@@ -1,5 +1,5 @@
 page.title=Samples
-page.image=images/cards/card-samples_2x.png
+page.image=images/cards/card-samples_16-9_2x.png
 @jd:body
 
 <p>
@@ -7,6 +7,7 @@
   Android SDK Manager under the <b>SDK Samples</b> component for the M Developer Preview.
 </p>
 
+<img src="{@docRoot}images/cards/card-google-cloud-messaging_16-9_2x" class="figure">
 <p class="note">
   <strong>Note:</strong> These downloadable projects are designed
    for use with Gradle and Android Studio.