Add download button to MediaDocument on Android.

third_party/WebKit/Source/core/css/html.css

Index: third_party/WebKit/Source/core/css/html.css
diff --git a/third_party/WebKit/Source/core/css/html.css b/third_party/WebKit/Source/core/css/html.css
index 9b6161af2510587ee121e9c0b900538db1378156..fc2e4ad539bb3e51dc2ef2292b3d25ce055797e9 100644
--- a/third_party/WebKit/Source/core/css/html.css
+++ b/third_party/WebKit/Source/core/css/html.css
@@ -63,6 +63,33 @@ body:-webkit-full-page-media {
     background-color: rgb(0, 0, 0)
 }
 
+body:-webkit-full-page-media > div > a {

[esprehn, 2016/03/15 17:33:07]

We can't do this. It adds rules for every <a> in every page. And marks bits on
the ancestors, it means children of all divs that contain anchors also stop
style sharing. You can add a class name or id instead. I think I'd rather you
just put this in a style element in the media document not here.

[qinmin, 2016/03/15 17:52:16]

Done. Moved the style back into MediaDocument

+    display: block;
+    width: 120px;
+    height: 36px;
+    background: #4285F4;
+    font-family: Roboto;
+    font-size: 14px;
+    border-radius: 5px;
+    color: white;
+    font-weight: bold;
+    text-decoration: none;
+    text-transform: uppercase;
+    text-align: center;
+    line-height: 36px;
+    margin: 32px auto 0 auto;
+}
+
+body:-webkit-full-page-media > div {

[esprehn, 2016/03/15 17:33:07]

Ditto, you can't put generic rules or use combinators like this in the UA sheet.

[qinmin, 2016/03/15 17:52:16]

Done.

+    max-height: 100%;
+    max-width: 100%;
+    position: absolute;
+    top: 50%;
+    left: 50%;
+    margin-right: -50%;
+    transform: translate(-50%, -50%);
+}
+
 p {
     display: block;
     -webkit-margin-before: 1__qem;