Make WebView work for external displays (over Presentations).

ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java

Index: ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
diff --git a/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java b/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
index 128d961758c91f5146e80d9b254338a9393e22d0..f9e8f91b44a84784a283ab52a6bd285e7bda9193 100644
--- a/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
+++ b/ui/android/java/src/org/chromium/ui/base/ActivityWindowAndroid.java
@@ -7,6 +7,7 @@ package org.chromium.ui.base;
 import android.app.Activity;
 import android.app.PendingIntent;
 import android.content.ActivityNotFoundException;
+import android.content.Context;
 import android.content.Intent;
 import android.content.IntentSender.SendIntentException;
 import android.content.SharedPreferences;
@@ -58,7 +59,7 @@ public class ActivityWindowAndroid
      * @param activity The activity associated with the WindowAndroid.
      */
     public ActivityWindowAndroid(Activity activity) {
-        this(activity, true);
+        this(activity, true, activity.getApplicationContext());

[boliu, 2015/07/15 06:38:46]

Should this just be activity? Why is displayContext the application context
here?

And if that's the case, activity and displayContext are always equal, so don't
need to add the new param below.

[gsennton, 2015/07/15 19:26:21]

activity and displayContext are not always equal (see AwContents.java) --
especially, in the case where we target an external display the two will not be
equal since then the displayContext will have been create through
Context.createDisplayContext(Display).
I guess that means that we should never create an ActivityWindowAndroid when
targeting an external display (since we only do that in AwContents when our
Context is an instance of Activity) and in that case we only need to worry about
displayContext in WindowAndroid and not in ActivityWindowAndroid?

[boliu, 2015/07/16 14:36:56]

Wait. How do you get to that display context from an activity then? I hope it's
not activity.getApplicationContext. It's not the activity itself?
Not including Services, there are only two kinds of context: the global
ApplicationContext, and we create WindowAndroid for that, and Activity, and we
create ActivityWindowAndroid for that.

So shouldn't it possible for an activity to belong to an external display? In
that case, we should create an ActivityWindowAndroid, but like I ask above, I
don't know what the "display context" should be.

[gsennton, 2015/10/20 13:27:12]

In PS11 we pass the activity to the WindowAndroid ctor which means that the
activity will be used as the display context.

So if an Activity can be made to target a different display it will now do so
properly (and if it can't then there was no problem regarding Activities in the
first place). 

...

[boliu, 2015/10/20 15:07:22]

Looks good.

     }
 
     /**
@@ -66,8 +67,9 @@ public class ActivityWindowAndroid
      * @param activity The activity associated with the WindowAndroid.
      * @param listenToActivityState Whether to listen to activity state changes.
      */
-    public ActivityWindowAndroid(Activity activity, boolean listenToActivityState) {
-        super(activity.getApplicationContext());
+    public ActivityWindowAndroid(
+            Activity activity, boolean listenToActivityState, Context displayContext) {
+        super(activity.getApplicationContext(), displayContext);
         mActivityRef = new WeakReference<Activity>(activity);
         mHandler = new Handler();
         mOutstandingPermissionRequests = new SparseArray<PermissionCallback>();