Enable WebVR presentation from Chrome Custom Tab

chrome/android/java/AndroidManifest.xml

Index: chrome/android/java/AndroidManifest.xml
diff --git a/chrome/android/java/AndroidManifest.xml b/chrome/android/java/AndroidManifest.xml
index 45f9a379cb9906a64f7cd2a06ed8f63c5e0bb0ef..a2339608a6c05521ae8f74ef6f29156eab3f6f15 100644
--- a/chrome/android/java/AndroidManifest.xml
+++ b/chrome/android/java/AndroidManifest.xml
@@ -48,6 +48,7 @@ by a child template that "extends" this file.
     <uses-permission android:name="android.permission.READ_SYNC_STATS"/>
     <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
     <uses-permission android:name="android.permission.RECORD_AUDIO"/>
+    <uses-permission android:name="android.permission.REORDER_TASKS"/>

[Ted C, 2017/03/31 18:17:18]

@yusufo -- We already have task moveToFront in ActivityDelegateImpl, but I'm
wondering if that is different.  Since this is manipulating CCTs, the task ID
might not be something Chrome owns (since the root task would be something like
gmail).  In that case, the getAppTasks from ActivityManager wouldn't return the
CCT one?

     <uses-permission android:name="android.permission.USE_CREDENTIALS"/>
     <uses-permission android:name="android.permission.VIBRATE"/>
     <uses-permission android:name="android.permission.WAKE_LOCK"/>
@@ -367,41 +368,7 @@ by a child template that "extends" this file.
             {% block supports_video_persistence %}
             {% endblock %}
             >
-            <!--
-              See the VRChromeTabbedActivity alias below for an explanation of this dummy intent
-              filter. We need to add these filters here as well, or non-presenting webVR pages will
-              trigger a daydream incompatible app message.
-            -->
-            <intent-filter>
-                <action android:name="org.chromium.chrome.browser.dummy.action" />
-                <category android:name="com.google.intent.category.DAYDREAM" />
-                <category android:name="com.google.intent.category.CARDBOARD" />
-            </intent-filter>
         </activity>
-
-        {% if enable_vr == "true" %}
-        <!--
-            TODO(mthiesse): Temporarily skip ChromeLauncherActivity when returning from Daydream
-            DON flow to avoid polluting metrics.
-        -->
-        <activity-alias android:name="org.chromium.chrome.browser.VRChromeTabbedActivity"
-            android:targetActivity="org.chromium.chrome.browser.ChromeTabbedActivity"
-            android:enableVrMode="@string/gvr_vr_mode_component">
-            <!--
-              Daydream api categorizes an activity to three categories: Cardboard only, hybrid
-              or Daydream. It does so by testing if intents can be resolved by the activity
-              that requests it.
-              In Chrome, CTA is the activity that uses Daydream api and we want to be in hybrid
-              category. So add an intent filter that could pass Daydream tests here.
-            -->
-            <intent-filter>
-                <action android:name="org.chromium.chrome.browser.dummy.action" />
-                <category android:name="com.google.intent.category.DAYDREAM" />
-                <category android:name="com.google.intent.category.CARDBOARD" />
-            </intent-filter>
-        </activity-alias>
-        {% endif %}
-
         <activity android:name="org.chromium.chrome.browser.ChromeTabbedActivity2"
              android:theme="@style/TabbedModeTheme"
              android:exported="false"
@@ -632,6 +599,27 @@ by a child template that "extends" this file.
             android:excludeFromRecents="true">
         </activity>
 
+        {% if enable_vr == "true" %}
+        <!-- Activity for dispatching intents to VR-enabled ChromeActivitys. This is necessary
+             because we can't return to CCT via a pendingIntent, which is how Daydream normally
+             launches an app after the DON flow. -->
+        <activity android:name="org.chromium.chrome.browser.vr_shell.VrProxyActivity"
+            android:exported="false"
+            android:theme="@android:style/Theme.NoDisplay"
+            android:noHistory="true"
+            android:excludeFromRecents="true"
+            android:relinquishTaskIdentity="true"
+            android:taskAffinity=""
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|mcc|mnc|screenLayout|smallestScreenSize|uiMode" >
+            android:launchMode="singleInstance">
+            <intent-filter>
+                <action android:name="org.chromium.chrome.browser.dummy.action" />
+                <category android:name="com.google.intent.category.DAYDREAM" />
+                <category android:name="com.google.intent.category.CARDBOARD" />
+            </intent-filter>
+        </activity>
+        {% endif %}
+
         <!-- Service for handling Nearby Messages -->
         <service android:name="org.chromium.chrome.browser.physicalweb.NearbyMessageIntentService"
             android:exported="false" />