Make WebView work for external displays (over Presentations).

content/public/android/java/src/org/chromium/content/browser/ScreenOrientationListener.java

Index: content/public/android/java/src/org/chromium/content/browser/ScreenOrientationListener.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/ScreenOrientationListener.java b/content/public/android/java/src/org/chromium/content/browser/ScreenOrientationListener.java
index 79b8ddbb7b366045c553d47fd21c89c4c55d0211..43e4a33017aa3273ed77bbf5d77a72f8c4bb434b 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ScreenOrientationListener.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ScreenOrientationListener.java
@@ -18,7 +18,6 @@ import android.view.WindowManager;
 import org.chromium.base.ObserverList;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.VisibleForTesting;
-import org.chromium.ui.gfx.DeviceDisplayInfo;
 
 /**
  * ScreenOrientationListener is a class that informs its observers when the
@@ -319,7 +318,7 @@ public class ScreenOrientationListener {
             return;
         }
 
-        DeviceDisplayInfo.create(mAppContext).updateNativeSharedDisplayInfo();
+        // TODO if we cache DeviceDisplayInfo then update the caches here

[boliu, 2015/06/01 15:30:18]

Hmm, this means native device_display_info shouldn't cache any results, and
should always go through jni to ask the java side. Otherwise anything caching a
device_display_info would get the wrong value after rotation?

(Gosh this was a big hack before)

[gsennton, 2015/06/04 14:10:29]

What's the problem with updating the caches here? (crbug.com/265008 suggests
that we should cache DeviceDisplayInfo)

[boliu, 2015/06/05 04:57:51]

Caching is fine.

The problem is ui/gfx is its own standalone component. It shouldn't need a
higher level construct in content to keep it working. So the right solution is
to have ui/gfx listen to orientation change events, and keep itself up-to-date.

 
         for (ScreenOrientationObserver observer : mObservers) {
             observer.onScreenOrientationChanged(mOrientation);