Use PrintWindow() to implement snapshots on windows 8.1+

ui/snapshot/snapshot_aura.cc

 // Copyright (c) 2012 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 "ui/snapshot/snapshot.h"
+#include "ui/snapshot/snapshot_aura.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/memory/ptr_util.h"
 #include "base/task_runner_util.h"
 #include "cc/output/copy_output_request.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_tracker.h"
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/dip_util.h"
 #include "ui/compositor/layer.h"
 #include "ui/snapshot/snapshot_async.h"
 
 namespace ui {
 
-bool GrabViewSnapshot(gfx::NativeView view,
-                      const gfx::Rect& snapshot_bounds,
-                      gfx::Image* image) {
-  return GrabWindowSnapshot(view, snapshot_bounds, image);
-}
-
-bool GrabWindowSnapshot(gfx::NativeWindow window,
-                        const gfx::Rect& snapshot_bounds,
-                        gfx::Image* image) {
+bool GrabWindowSnapshotAura(aura::Window* window,
+                            const gfx::Rect& snapshot_bounds,
+                            gfx::Image* image) {
   // Not supported in Aura.  Callers should fall back to the async version.
   return false;
 }
 
 static void MakeAsyncCopyRequest(
-    gfx::NativeWindow window,
+    aura::Window* window,
     const gfx::Rect& source_rect,
     const cc::CopyOutputRequest::CopyOutputRequestCallback& callback) {
   std::unique_ptr<cc::CopyOutputRequest> request =
       cc::CopyOutputRequest::CreateBitmapRequest(callback);
   request->set_area(source_rect);
   window->layer()->RequestCopyOfOutput(std::move(request));
 }
 
 static void FinishedAsyncCopyRequest(
     std::unique_ptr<aura::WindowTracker> tracker,
     const gfx::Rect& source_rect,
     const cc::CopyOutputRequest::CopyOutputRequestCallback& callback,
     int retry_count,
     std::unique_ptr<cc::CopyOutputResult> result) {
   static const int kMaxRetries = 5;
   // Retry the copy request if the previous one failed for some reason.
   if (!tracker->windows().empty() && (retry_count < kMaxRetries) &&
       result->IsEmpty()) {
     // Look up window before calling MakeAsyncRequest. Otherwise, due
     // to undefined (favorably right to left) argument evaluation
     // order, the tracker might have been passed and set to NULL
     // before the window is looked up which results in a NULL pointer
     // dereference.
-    gfx::NativeWindow window = tracker->windows()[0];
+    aura::Window* window = tracker->windows()[0];
     MakeAsyncCopyRequest(
         window, source_rect,
         base::Bind(&FinishedAsyncCopyRequest, base::Passed(&tracker),
                    source_rect, callback, retry_count + 1));
     return;
   }
 
   callback.Run(std::move(result));
 }
 
 static void MakeInitialAsyncCopyRequest(
-    gfx::NativeWindow window,
+    aura::Window* window,
     const gfx::Rect& source_rect,
     const cc::CopyOutputRequest::CopyOutputRequestCallback& callback) {
   auto tracker = base::MakeUnique<aura::WindowTracker>();
   tracker->Add(window);
   MakeAsyncCopyRequest(
       window, source_rect,
       base::Bind(&FinishedAsyncCopyRequest, base::Passed(&tracker), source_rect,
                  callback, 0));
 }
 
-void GrabWindowSnapshotAndScaleAsync(
-    gfx::NativeWindow window,
+void GrabWindowSnapshotAndScaleAsyncAura(
+    aura::Window* window,
     const gfx::Rect& source_rect,
     const gfx::Size& target_size,
     scoped_refptr<base::TaskRunner> background_task_runner,
     const GrabWindowSnapshotAsyncCallback& callback) {
   MakeInitialAsyncCopyRequest(
       window, source_rect,
       base::Bind(&SnapshotAsync::ScaleCopyOutputResult, callback, target_size,
                  background_task_runner));
 }
 
+void GrabWindowSnapshotAsyncAura(
+    aura::Window* window,
+    const gfx::Rect& source_rect,
+    const GrabWindowSnapshotAsyncCallback& callback) {
+  MakeInitialAsyncCopyRequest(
+      window, source_rect,
+      base::Bind(&SnapshotAsync::RunCallbackWithCopyOutputResult, callback));
+}
+
+#if !defined(OS_WIN)
+bool GrabWindowSnapshot(gfx::NativeWindow window,
+                        const gfx::Rect& snapshot_bounds,
+                        gfx::Image* image) {
+  // Not supported in Aura.  Callers should fall back to the async version.
+  return false;
+}
+
+bool GrabViewSnapshot(gfx::NativeView view,
+                      const gfx::Rect& snapshot_bounds,
+                      gfx::Image* image) {
+  return GrabWindowSnapshot(view, snapshot_bounds, image);
+}
+
+void GrabWindowSnapshotAndScaleAsync(
+    gfx::NativeWindow window,
+    const gfx::Rect& source_rect,
+    const gfx::Size& target_size,
+    scoped_refptr<base::TaskRunner> background_task_runner,
+    const GrabWindowSnapshotAsyncCallback& callback) {
+  GrabWindowSnapshotAndScaleAsyncAura(window, source_rect, target_size,
+                                      background_task_runner, callback);
+}
+
 void GrabWindowSnapshotAsync(gfx::NativeWindow window,
                              const gfx::Rect& source_rect,
                              const GrabWindowSnapshotAsyncCallback& callback) {
-  MakeInitialAsyncCopyRequest(
-      window, source_rect,
-      base::Bind(&SnapshotAsync::RunCallbackWithCopyOutputResult, callback));
+  GrabWindowSnapshotAsyncAura(window, source_rect, callback);
 }
 
 void GrabViewSnapshotAsync(gfx::NativeView view,
                            const gfx::Rect& source_rect,
                            const GrabWindowSnapshotAsyncCallback& callback) {
-  GrabWindowSnapshotAsync(view, source_rect, callback);
+  GrabWindowSnapshotAsyncAura(view, source_rect, callback);
 }
 
+#endif
 
 }  // namespace ui