docs: update template and css for android u
Add a custom version of docpage.cs to the droiddoc template, because
it adds a good deal of custom design and behavior (instead of updating
the doclava version of the file). Add CSS for next/previous links in
android u lessons and revise style for download button.

Change-Id: I829c4fb134d6f5c3cee82fb86958d23ef64e8481
diff --git a/tools/droiddoc/templates-sdk/assets/android-developer-docs.css b/tools/droiddoc/templates-sdk/assets/android-developer-docs.css
index 4e759da..2e15a68 100644
--- a/tools/droiddoc/templates-sdk/assets/android-developer-docs.css
+++ b/tools/droiddoc/templates-sdk/assets/android-developer-docs.css
@@ -1038,78 +1038,138 @@
 
 div#tb-wrapper {
   float: right;
-  width:480px; /* +25px padding = 505 */
+  clear:right;
+  width:380px; /* +25px padding = 405 */
   background-color:#fff;
-  margin:-48px 0 2px 0;
+  margin:0 0 2px 0;
   padding:0 0 20px 25px;
 }
 
 div#tb {
   margin:0;
-  padding:15px;
-  width:450px; /* +15px padding = 480 */
+  padding:0 15px;
+  width:350px; /* +15px padding = 380 */
   font-size:.9em;
   background:#e9e9e9;
+  border:1px solid #aaa;
   border-radius:5px;
   -moz-border-radius:5px;
   -webkit-border-radius:5px;
+  overflow:auto;
 }
 
 div#tb h2 {
   font-size:1.3em;
   font-weight:bold;
-  margin:12px 0 .25em 0;
-  padding:10px 0;
+  margin:1em 0;
+  padding:0;
   background-color:transparent;
   border:none;
+  clear:both;
 }
 
 div.download-box a.button {
-  color:#eee;
-  font-weight:bold;
+  color: #069;
   font-size:1.1em;
+  font-weight:bold;
   text-decoration:none;
-  height:40px;
-  line-height:40px;
-  padding:5px 10px;
-  border:2px solid #99be27;
-  border-radius:5px;
-  -moz-border-radius:5px;
-  -webkit-border-radius:5px;
-  /* thanks http://www.colorzilla.com/gradient-editor/ */
-  background: #aed33c; /* Old browsers */
-  background: -moz-linear-gradient(top, #aed33c 20%, #a1c730 80%); /* FF3.6+ */
-  background: -webkit-gradient(linear, left top, left bottom, color-stop(20%,#aed33c), color-stop(80%,#a1c730)); /* Chrome,Safari4+ */
-  background: -webkit-linear-gradient(top, #aed33c 20%,#a1c730 80%); /* Chrome10+,Safari5.1+ */
-  background: -o-linear-gradient(top, #aed33c 20%,#a1c730 80%); /* Opera11.10+ */
-  background: -ms-linear-gradient(top, #aed33c 20%,#a1c730 80%); /* IE10+ */
-  filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#AED33C', endColorstr='#A1C730',GradientType=0 ); /* IE6-9 */
-  background: linear-gradient(top, #aed33c 20%,#a1c730 80%); /* W3C */
+  height:27px;
+  line-height:27px;
+  text-align:center;
+  padding:5px 8px;
+  background-color: #fff;
+  border: 1px solid #aaa;
+  -webkit-border-radius: 2px;
+  -moz-border-radius: 2px;
+  border-radius: 2px;
 }
 
 div.download-box a.button:hover {
-  border:2px solid #b2d841;
+  border-color: #09C;
+  background-color: #4CADCB;
+  background-image: -webkit-gradient(linear,left top,left bottom,from(#5dbcd9),to(#4cadcb));
+  background-image: -webkit-linear-gradient(top,#5dbcd9,#4cadcb);
+  background-image: -moz-linear-gradient(top,#5dbcd9,#4cadcb);
+  background-image: -ms-linear-gradient(top,#5dbcd9,#4cadcb);
+  background-image: -o-linear-gradient(top,#5dbcd9,#4cadcb);
+  background-image: linear-gradient(top,#5dbcd9,#4cadcb);
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#5dbcd9',EndColorStr='#4cadcb');
+  color: #fff;
 }
 
 div.download-box a.button:active {
-  background: #a1c730; /* Old browsers */
-  background: -moz-linear-gradient(top, #a1c730 15%, #aed33c 70%); /* FF3.6+ */
-  background: -webkit-gradient(linear, left top, left bottom, color-stop(15%,#a1c730), color-stop(70%,#aed33c)); /* Chrome,Safari4+ */
-  background: -webkit-linear-gradient(top, #a1c730 15%,#aed33c 70%); /* Chrome10+,Safari5.1+ */
-  background: -o-linear-gradient(top, #a1c730 15%,#aed33c 70%); /* Opera11.10+ */
-  background: -ms-linear-gradient(top, #a1c730 15%,#aed33c 70%); /* IE10+ */
-  filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#a1c730', endColorstr='#aed33c',GradientType=0 ); /* IE6-9 */
-  background: linear-gradient(top, #a1c730 15%,#aed33c 70%); /* W3C */
+  background-color: #1E799A;
+  background-image: none;
+  border-color: #30B7E6;
 }
 
 div.download-box p.filename {
-  font-size:0.8em;
+  font-size:0.85em;
   color:#888;
-  margin:0 0 0 12px;
+  margin:4px 0 1em 10px;
 }
 
 /* End developer training bar */
 
+/* Training nav bar (previous/next) */
+
+div.training-nav-top {
+  float: right;
+  width:380px; /* +25px padding = 405 */
+  margin:-58px 0 0 0;
+  padding:0 0 20px 25px;
+}
+
+div.training-nav-bottom {
+  padding:1px; /* for weird FF bug (scrollbar appears) */
+  margin:3em 0;
+  overflow:auto;
+}
+
+div.training-nav-button-next a,
+div.training-nav-button-previous a {
+  display:block;
+  width:160px;
+  height:55px;
+  padding:4px 7px;
+  border:1px solid #aaa;
+  border-radius:5px;
+  -moz-border-radius:5px;
+  -webkit-border-radius:5px;
+  text-decoration:none;
+  font-weight:bold;
+}
+
+div.training-nav-button-next a:hover,
+div.training-nav-button-previous a:hover {
+  border:1px solid #069; /* match link color */
+}
+
+div.training-nav-button-next a:active,
+div.training-nav-button-previous a:active {
+  border:1px solid #f00; /* match link color */
+}
+  
+div.training-nav-button-previous {
+  float:left;
+  text-align:left;
+}
+
+div.training-nav-button-next {
+  float:right;
+  text-align:right;
+}
+
+span.training-nav-button-title {
+  display:block;
+  font-size:.85em;
+  font-weight:normal;
+  line-height:1.3em;
+  margin:.5em 0 0;
+}
+
+/* End training nav bar */
+
 /* BEGIN image and caption styles (originally for UI Guidelines docs) */
 
 table.image-caption {