Implement new compositor and ContentViewCore reparenting for VR Shell.

chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java

Index: chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
index 46a55a1fa806a86f66f032cb89be127d95396dac..9e66af9d65ddc0880776caa0f6a3c9f81b0dd481 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
@@ -15,6 +15,7 @@ import android.view.WindowManager;
 
 import org.chromium.base.Log;
 import org.chromium.chrome.browser.ChromeTabbedActivity;
+import org.chromium.chrome.browser.tab.Tab;
 
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
@@ -71,6 +72,12 @@ public class VrShellDelegate {
      */
     public boolean enterVRIfNecessary() {
         if (!mVrShellEnabled) return false;
+        Tab tab = mActivity.getActivityTab();
+        // TODO(mthiesse): When we have VR UI for opening new tabs, etc., allow VR Shell to be
+        // entered without any current tabs.
+        if (tab == null || tab.getContentViewCore() == null) {
+            return false;
+        }
         if (mInVr) return true;
         // VrShell must be initialized in Landscape mode due to a bug in the GVR library.
         mActivity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
@@ -80,7 +87,7 @@ public class VrShellDelegate {
         }
         addVrViews();
         setupVrModeWindowFlags();
-        mVrShellView.onNativeLibraryReady();
+        mVrShellView.onNativeLibraryReady(tab);
         mVrShellView.setVrModeEnabled(true);
         mInVr = true;
         return true;
@@ -120,8 +127,10 @@ public class VrShellDelegate {
     private boolean createVrShell() {
         StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
         try {
-            Constructor<?> vrShellConstructor = mVrShellClass.getConstructor(Activity.class);
-            mVrShellView = (VrShellInterface) vrShellConstructor.newInstance(mActivity);
+            Constructor<?> vrShellConstructor = mVrShellClass.getConstructor(Activity.class,
+                                                                             ViewGroup.class);
+            mVrShellView = (VrShellInterface) vrShellConstructor.newInstance(mActivity,
+                                                                             mParentView);
         } catch (InstantiationException | IllegalAccessException | IllegalArgumentException
                 | InvocationTargetException | NoSuchMethodException e) {
             Log.e(TAG, "Unable to instantiate VrShell", e);
@@ -136,9 +145,11 @@ public class VrShellDelegate {
         LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT,
                 LayoutParams.MATCH_PARENT);
         mParentView.addView(mVrShellView.getContainer(), mParentView.getChildCount(), params);
+        mActivity.setUIVisibilityForVR(View.GONE);

[amp, 2016/09/12 22:36:53]

I read this now as saying it's setting the VR visibility to GONE.

How about something like setDefaultUIVisibility?

[mthiesse, 2016/09/13 19:04:04]

I think setUIVisibilityForVR makes sense in the context of ChromeTabbedActivity,
whereas setDefaultUIVisibility doesn't really make sense as we're not setting
any defaults.

     }
 
     private void removeVrViews() {
+        mActivity.setUIVisibilityForVR(View.VISIBLE);
         ((ViewGroup) mVrShellView.getContainer().getParent())
                 .removeView(mVrShellView.getContainer());
     }