Support "display": "fullscreen" for sites added to the home screen.

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java
index 7a35c67a8ce7a90cbdfc875aec890b77f31d55d4..8fe9c3fa3b0c84f5ef6e37ab785d9d777a6b9c51 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java
@@ -117,10 +117,16 @@ public class WebappActivity extends FullScreenActivity {
         }
 
         getActivityTab().addObserver(createTabObserver());
-        getActivityTab().getTabWebContentsDelegateAndroid().setDisplayMode(
-                WebDisplayMode.Standalone);
-        // TODO(dominickn): send the web app into fullscreen if mDisplayMode is
-        // WebDisplayMode.Fullscreen. See crbug.com/581522
+
+        // Add Fullscreen support and the other modes will fallback to Standalone.

[dominickn, 2017/01/18 05:56:17]

Nit: the comment here probably isn't necessary (the code is very descriptive).
Also, in the future there will also be display:minimal-ui. That currently falls
back to a browser tab.

[Leo, 2017/01/18 23:03:12]

Acknowledged.

+        if (mWebappInfo.displayMode() == WebDisplayMode.Fullscreen) {
+            getActivityTab().getTabWebContentsDelegateAndroid().setDisplayMode(
+                    WebDisplayMode.Fullscreen);
+            enterImmersiveMode(getWindow().getDecorView());
+        } else {
+            getActivityTab().getTabWebContentsDelegateAndroid().setDisplayMode(
+                    WebDisplayMode.Standalone);
+        }
     }
 
     @Override