Hide mouse cursor when screenshot is taking

BUG=597270
TEST=device test saw bug away

Review-Url: https://codereview.chromium.org/2167613003
Cr-Commit-Position: refs/heads/master@{#407325}

ui/snapshot/screenshot_grabber.cc

@@ -24,6 +24,7 @@
 #include "ui/snapshot/snapshot.h"
 
 #if defined(USE_AURA)
+#include "ui/aura/client/cursor_client.h"
 #include "ui/aura/window.h"
 #endif
 
@@ -108,6 +109,35 @@ void ScreenshotGrabberDelegate::PrepareFileAndRunOnBlockingPool(
       base::Bind(EnsureLocalDirectoryExists, path, callback_on_blocking_pool));
 }
 
+#if defined(USE_AURA)
+class ScreenshotGrabber::ScopedCursorHider {
+ public:
+  // The nullptr might be returned when GetCursorClient is nullptr.
+  static std::unique_ptr<ScopedCursorHider> Create(aura::Window* window) {
+    DCHECK(window->IsRootWindow());
+    aura::client::CursorClient* cursor_client =
+        aura::client::GetCursorClient(window);
+    if (!cursor_client)
+      return nullptr;
+    cursor_client->HideCursor();
+    return std::unique_ptr<ScopedCursorHider>(
+        base::WrapUnique(new ScopedCursorHider(window)));
+  }
+
+  ~ScopedCursorHider() {
+    aura::client::CursorClient* cursor_client =
+        aura::client::GetCursorClient(window_);
+    cursor_client->ShowCursor();
+  }
+
+ private:
+  explicit ScopedCursorHider(aura::Window* window) : window_(window) {}
+  aura::Window* window_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedCursorHider);
+};
+#endif
+
 ScreenshotGrabber::ScreenshotGrabber(
     ScreenshotGrabberDelegate* client,
     scoped_refptr<base::TaskRunner> blocking_task_runner)
@@ -134,6 +164,8 @@ void ScreenshotGrabber::TakeScreenshot(gfx::NativeWindow window,
   aura::Window* aura_window = static_cast<aura::Window*>(window);
   is_partial = rect.size() != aura_window->bounds().size();
   window_identifier = aura_window->GetBoundsInScreen().ToString();
+
+  cursor_hider_ = ScopedCursorHider::Create(aura_window->GetRootWindow());
 #endif
   ui::GrabWindowSnapshotAsync(
       window, rect, blocking_task_runner_,
@@ -152,6 +184,9 @@ void ScreenshotGrabber::NotifyScreenshotCompleted(
     ScreenshotGrabberObserver::Result screenshot_result,
     const base::FilePath& screenshot_path) {
   DCHECK(base::MessageLoopForUI::IsCurrent());
+#if defined(USE_AURA)
+  cursor_hider_.reset();
+#endif
   FOR_EACH_OBSERVER(ScreenshotGrabberObserver, observers_,
                     OnScreenshotCompleted(screenshot_result, screenshot_path));
 }

ui/snapshot/screenshot_grabber.h

@@ -76,6 +76,10 @@ class SNAPSHOT_EXPORT ScreenshotGrabber {
   bool HasObserver(const ScreenshotGrabberObserver* observer) const;
 
  private:
+#if defined(USE_AURA)
+  class ScopedCursorHider;
+#endif
+
   void GrabWindowSnapshotAsyncCallback(
       const std::string& window_identifier,
       base::FilePath screenshot_path,
@@ -91,6 +95,11 @@ class SNAPSHOT_EXPORT ScreenshotGrabber {
   // Task runner for blocking tasks.
   scoped_refptr<base::TaskRunner> blocking_task_runner_;
 
+#if defined(USE_AURA)
+  // The object to hide cursor when taking screenshot.
+  std::unique_ptr<ScopedCursorHider> cursor_hider_;
+#endif
+
   base::ObserverList<ScreenshotGrabberObserver> observers_;
   base::WeakPtrFactory<ScreenshotGrabber> factory_;