android: content::UIResourceProvider and content::UIResourceClientAndroid

content/public/browser/android/ui_resource_listener.h

Index: content/public/browser/android/ui_resource_listener.h
diff --git a/content/public/browser/android/ui_resource_listener.h b/content/public/browser/android/ui_resource_listener.h
new file mode 100644
index 0000000000000000000000000000000000000000..37e96507ad6ede9089f2b66a5f128bfb2b3f93b7
--- /dev/null
+++ b/content/public/browser/android/ui_resource_listener.h
@@ -0,0 +1,29 @@
+// Copyright 2014 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 CONTENT_PUBLIC_BROWSER_ANDROID_UI_RESOURCE_LISTENER_H_
+#define CONTENT_PUBLIC_BROWSER_ANDROID_UI_RESOURCE_LISTENER_H_
+
+#include "base/containers/hash_tables.h"
+#include "content/common/content_export.h"
+
+namespace content {
+
+class UIResourceProvider;
+
+class CONTENT_EXPORT UIResourceListener {
+ public:
+  // Called when the UI resources allocated through the provider are no longer
+  // valid.
+  virtual void OnUIResourcesAreInvalid() = 0;
+
+  // Signals that the UIResourceProvider is ready for the listeners to create UI
+  // resources. This typically happens after the invalidation of the UI
+  // resources.
+  virtual void OnRecreateUIResources() = 0;

[David Trainor- moved to gerrit, 2014/05/16 18:18:35]

Ah the comment makes these names a little more clear.  Maybe ignore my comment
downstream.

[no sievers, 2014/05/16 20:12:19]

Do we even need this?
You cannot create UI resources while the Compositor is hidden (or has no
surface) which is more or less under the app's control anyway.

Or the UIResourceProvider could just hold on to the resources until the host is
ready.

[no sievers, 2014/05/16 20:22:36]

Also, how do we currently handle it to make sure that UIResources were passed
before we start rendering, or rather the compositor is set to visible?

[powei, 2014/05/19 18:49:46]

Some users prefer to throw the bitmap away as soon as it has been uploaded as
resource (large bitmaps like thumbnails).  The provider holding on to the bitmap
seems counter to that.

[powei, 2014/05/19 18:49:46]

Updates to the various resource managers are called before every frame to make
sure that the resources are up to date.

+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_ANDROID_UI_RESOURCE_LISTENER_H_