Add VoiceInteractionFrameworkHost::SetMetalayerEnabled

components/arc/common/voice_interaction_framework.mojom

 // Copyright 2017 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.
 //
-// Next MinVersion: 3
+// Next MinVersion: 4
 
 module arc.mojom;
 
 import "screen_rect.mojom";
 
 // Handles voice interaction queries from Android.
-// Next method ID: 3
+// Next method ID: 4
 interface VoiceInteractionFrameworkHost {
   // Returns a screenshot of currently focused window or empty array if
   // no window is focused. |data| represents the image encoded in JPEG
   // format.
   CaptureFocusedWindow@0() => (array<uint8> data);
 
   // Returns a fullscreen screenshot of the primary display.
   // |data| represents the image encoded in JPEG format.
   [MinVersion=1]CaptureFullscreen@1() => (array<uint8> data);
 
   // Notifies the host that the metalayer has closed or could not open.
   [MinVersion=2]OnMetalayerClosed@2();
+
+  // Enables/disables screenshot taking.
+  [MinVersion=3]SetMetalayerEnabled@3(bool enabled);

[estark, 2017/05/11 01:14:13]

Does untrusted code call this, or only trusted code? Naively, it sounds bad if
untrusted code can enable screenshot-taking and get a screenshot of the current
focused window.

 };
 
 // Connects with Android system server.
 // Next method ID: 4
 interface VoiceInteractionFrameworkInstance {
   Init@0(VoiceInteractionFrameworkHost host_ptr);
 
   // Starts the voice interaction session in container.
   StartVoiceInteractionSession@1();
 
   // Starts the voice interaction session in container, with a screen region
   // selected.
   [MinVersion=1] StartVoiceInteractionSessionForRegion@2(ScreenRect region);
 
   // Shows/hides the metalayer in the container.
   [MinVersion=1] SetMetalayerVisibility@3([MinVersion=2] bool visible);
 };