Autopresent WebVR content in CCT if it was opened by a Daydream Intent

chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
index 83310c0fda73c0642f86fd6cd2850eceb5573c88..f903409f577ff868c8f542d724b316d442dfe7bb 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
@@ -632,6 +632,14 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
     }
 
     /**
+     * @return Whether this activity should automatically present WebVR content in fullscreen
+     *         binocular rendering mode. Normally, presentation needs a user gesture.
+     */
+    public boolean shouldAutoPresent() {

[mthiesse, 2017/04/21 14:24:27]

Maybe call this shouldAutoPresentOnVrIntent()?

[David Trainor- moved to gerrit, 2017/04/21 17:00:09]

supportsAutoPresent()?  If we're decoupling it from needing/checking the intent
maybe we just don't include that at all?

[mthiesse, 2017/04/21 17:03:23]

supportsAutoPresent is probably fine, but we should be careful to make it clear
that this is a policy decision, and not a technical one. All ChromeActivitys
technically support autopresent, but we only want to enable it for CCT direct
linking.

[bshe, 2017/04/21 17:54:01]

I actually intentionally want to avoid associate this function to a specific
thing such as(intent) as I imagine that we will need auto present check in other
cases
in the future. And we probably don't want to have multiple
shouldAutoPresent(OnVrIntent|OnNavigation*) functions.

supportsAutoPresent is an option. But since all activity technically supports
auto present,
I think use shouldAutoPresent probably makes more sense?

[Yusuf, 2017/04/21 23:10:38]

It is just that what Present means is not clear from a general perspective. What
are we presenting here? Without the VR context, I dont really understand what
that means.

[bshe, 2017/04/24 13:59:12]

Present in VR means the activity entering into a mode which is similar to
fullscreen in the sense that 2D browser UI is invisible. And it also starts to
show left and right images on the screen. From this point, it only make sense to
view this activity in a VR headset like Cardboard.
The presented content is a WebVR content, which is essentially a WebGl canvas.
The canvas draws left and right images and presenting it on screen.
Hopefully, this answers your question. Please feel free to let me know if you
have any further questions.

+        return false;
+    }
+
+    /**
      * @return The {@link TabModelSelector} owned by this {@link ChromeActivity}.
      */
     protected abstract TabModelSelector createTabModelSelector();