Hold a reference to any kind of context in WindowAndroid.

ui/android/window_android.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_ANDROID_WINDOW_ANDROID_H_
 #define UI_ANDROID_WINDOW_ANDROID_H_
 
 #include <jni.h>
 #include <string>
 #include <vector>
@@ skipping 51 matching lines @@
                jlong period_micros);
   void OnVisibilityChanged(JNIEnv* env, jobject obj, bool visible);
   void OnActivityStopped(JNIEnv* env, jobject obj);
   void OnActivityStarted(JNIEnv* env, jobject obj);
 
   // Return whether the specified Android permission is granted.
   bool HasPermission(const std::string& permission);
   // Return whether the specified Android permission can be requested by Chrome.
   bool CanRequestPermission(const std::string& permission);
 
+  // This is public only for use from ResourceManager

[Ted C, 2015/10/29 22:39:19]

We specifically wanted to avoid exposing the context to anyone as it is
extremely easy to get the lifecycle wrong.

Despite having this comment, having this method here allows easy abuse and I
doubt it will stop anyone.

I think to keep it consistent with the ActivityWindowAndroid implementation, it
should return a JavaObjectWeakGlobalRef with very clear documentation that it
should never be held on to longer than the lifetime of the context (whatever
that may be).  For example, I know nothing of a Presentation context and do not
know if the resource manager lifecycle will match it exactly.

If it outlives it, then we're going to hold onto that and leak everything
attached to it.

[gsennton, 2015/11/06 17:36:13]

Done.

+  base::android::ScopedJavaLocalRef<jobject> GetJavaDisplayContext();
+
  private:
   ~WindowAndroid();
 
   base::android::ScopedJavaGlobalRef<jobject> java_window_;
   gfx::Vector2dF content_offset_;
   WindowAndroidCompositor* compositor_;
 
   base::ObserverList<WindowAndroidObserver> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowAndroid);
 };
 
 }  // namespace ui
 
 #endif  // UI_ANDROID_WINDOW_ANDROID_H_