Block incognito browser windows for voice interaction.

chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc

 // 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.
 
 #include "chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.h"
 
+#include <set>
 #include <utility>
 #include <vector>
 
 #include "ash/accelerators/accelerator_controller.h"
 #include "ash/shell.h"
+#include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/task_scheduler/post_task.h"
+#include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/browser_list.h"
+#include "chrome/browser/ui/browser_window.h"
 #include "chromeos/chromeos_switches.h"
 #include "components/arc/arc_bridge_service.h"
 #include "components/arc/instance_holder.h"
 #include "content/public/browser/browser_thread.h"
 #include "ui/aura/window.h"
+#include "ui/compositor/layer.h"
+#include "ui/compositor/layer_owner.h"
+#include "ui/compositor/layer_tree_owner.h"
+#include "ui/gfx/image/image.h"
+#include "ui/gfx/image/image_util.h"
+#include "ui/gfx/native_widget_types.h"
 #include "ui/snapshot/snapshot.h"
+#include "ui/snapshot/snapshot_aura.h"
+#include "ui/wm/core/window_util.h"
 #include "ui/wm/public/activation_client.h"
 
 namespace arc {
 
 namespace {
 
 void ScreenshotCallback(
     const mojom::VoiceInteractionFrameworkHost::CaptureFocusedWindowCallback&
         callback,
     scoped_refptr<base::RefCountedMemory> data) {
   if (data.get() == nullptr) {
     callback.Run(std::vector<uint8_t>{});
     return;
   }
   std::vector<uint8_t> result(data->front(), data->front() + data->size());
   callback.Run(result);
 }
 
+std::unique_ptr<ui::LayerTreeOwner> BlockIncognitoWindows(

[reveman, 2017/05/15 18:55:07]

Is blocking incognito windows the only thing this function does? I thought it
would also avoid to include the overlay. In that case maybe
CreateLayerTreeForSnapshot is a more appropriate name.

[Muyuan, 2017/05/15 19:09:08]

Done.

+    aura::Window* root_window) {
+  using LayerSet = std::set<const ui::Layer*>;

[reveman, 2017/05/15 18:55:07]

flat_set more appropriate?

[Muyuan, 2017/05/15 19:09:08]

Done.

+  LayerSet blocked_layers;
+  for (auto* browser : *BrowserList::GetInstance()) {
+    if (browser->profile()->IsOffTheRecord())
+      blocked_layers.insert(browser->window()->GetNativeWindow()->layer());
+  }
+
+  auto layer_tree_owner = ::wm::MapLayers(

[reveman, 2017/05/15 18:55:07]

Would it not be easier to re-implement the CloneChildren functionality here for
this specific use case instead complicating the RecreateLayers code in
window_util.cc? Maybe you can even avoid the blocked_layer set that way..

[Muyuan, 2017/05/15 19:09:08]

I feel that the logic used here is almost identical to CloneChildren and that's
why I generalized the code in RecreateLayers in window_utils to allow providing
a customized traversal function instead of copying pasting code of CloneChildren
back here.

+      root_window, base::Bind(
+                       [](LayerSet layers,
+                          ui::LayerOwner* owner) -> std::unique_ptr<ui::Layer> {
+                         // Parent layer is excluded meaning that it's pointless
+                         // to clone current child and all its descendants. This
+                         // reduces the number of layers to create.
+                         if (layers.count(owner->layer()->parent()))
+                           return nullptr;
+                         if (layers.count(owner->layer())) {
+                           auto layer = base::MakeUnique<ui::Layer>(
+                               ui::LayerType::LAYER_SOLID_COLOR);
+                           layer->SetBounds(owner->layer()->bounds());
+                           layer->SetColor(SK_ColorBLACK);
+                           return layer;
+                         }
+                         return owner->RecreateLayer();
+                       },
+                       std::move(blocked_layers)));
+
+  // layer_tree_owner cannot be null since we are starting off from the root
+  // window, which could never be incognito.
+  DCHECK(layer_tree_owner);
+
+  auto* root_layer = layer_tree_owner->root();
+  root_window->layer()->Add(root_layer);
+  root_window->layer()->StackAtBottom(root_layer);
+  return layer_tree_owner;
+}
+
+void EncodeAndReturnImage(
+    const ArcVoiceInteractionFrameworkService::CaptureFullscreenCallback&
+        callback,
+    std::unique_ptr<ui::LayerTreeOwner> old_layer_owner,
+    const gfx::Image& image) {
+  old_layer_owner.reset();
+  base::PostTaskWithTraitsAndReplyWithResult(
+      FROM_HERE,
+      base::TaskTraits{base::MayBlock(), base::TaskPriority::USER_BLOCKING},
+      base::Bind(
+          [](const gfx::Image& image) -> std::vector<uint8_t> {
+            std::vector<uint8_t> res;
+            gfx::JPEG1xEncodedDataFromImage(image, 100, &res);
+            return res;
+          },
+          image),
+      callback);
+}
+
 }  // namespace
 
 // static
 const char ArcVoiceInteractionFrameworkService::kArcServiceName[] =
     "arc::ArcVoiceInteractionFrameworkService";
 
 ArcVoiceInteractionFrameworkService::ArcVoiceInteractionFrameworkService(
     ArcBridgeService* bridge_service)
     : ArcService(bridge_service), binding_(this) {
   arc_bridge_service()->voice_interaction_framework()->AddObserver(this);
@@ skipping 79 matching lines @@
       base::Bind(&ScreenshotCallback, callback));
 }
 
 void ArcVoiceInteractionFrameworkService::CaptureFullscreen(
     const CaptureFullscreenCallback& callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   // Since ARC currently only runs in primary display, we restrict
   // the screenshot to it.
   aura::Window* window = ash::Shell::GetPrimaryRootWindow();
   DCHECK(window);
-  ui::GrabWindowSnapshotAsyncJPEG(
-      window, gfx::Rect(window->bounds().size()),
-      base::CreateTaskRunnerWithTraits(
-          {base::MayBlock(), base::TaskPriority::USER_BLOCKING}),
-      base::Bind(&ScreenshotCallback, callback));
+
+  auto old_layer_owner = BlockIncognitoWindows(window);
+  ui::GrabLayerSnapshotAsync(
+      old_layer_owner->root(), gfx::Rect(window->bounds().size()),
+      base::Bind(&EncodeAndReturnImage, callback,
+                 base::Passed(std::move(old_layer_owner))));
 }
 
 void ArcVoiceInteractionFrameworkService::OnMetalayerClosed() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (!metalayer_closed_callback_.is_null())
     base::ResetAndReturn(&metalayer_closed_callback_).Run();
 }
 
 void ArcVoiceInteractionFrameworkService::SetMetalayerEnabled(bool enabled) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
@@ skipping 36 matching lines @@
           SetMetalayerVisibility);
   if (!framework_instance) {
     if (!metalayer_closed_callback_.is_null())
       base::ResetAndReturn(&metalayer_closed_callback_).Run();
     return;
   }
   framework_instance->SetMetalayerVisibility(visible);
 }
 
 }  // namespace arc