Makes the visual feedback for taking screenshot.

chrome/browser/ui/views/aura/screenshot_taker.cc

Index: chrome/browser/ui/views/aura/screenshot_taker.cc
diff --git a/chrome/browser/ui/views/aura/screenshot_taker.cc b/chrome/browser/ui/views/aura/screenshot_taker.cc
index c004e9c736fb66c4022d03da8cd7c0549332872e..1a938c5b633df431b4df94771bec235f54e130f9 100644
--- a/chrome/browser/ui/views/aura/screenshot_taker.cc
+++ b/chrome/browser/ui/views/aura/screenshot_taker.cc
@@ -6,6 +6,8 @@
 
 #include <string>
 
+#include "ash/shell.h"
+#include "ash/shell_window_ids.h"
 #include "base/bind.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
@@ -64,6 +66,13 @@ void SaveScreenshot(bool is_logged_in,
   }
 }
 
+// How opaque should the layer that we flash onscreen to provide visual
+// feedback after the screenshot is taken be?
+const unsigned char kVisualFeedbackLayerOpacity = 64;
+
+// How long should the visual feedback layer be displayed?
+const int64 kVisualFeedbackLayerDisplayTimeMs = 100;
+
 }  // namespace
 
 ScreenshotTaker::ScreenshotTaker() {
@@ -81,6 +90,7 @@ void ScreenshotTaker::HandleTakePartialScreenshot(
 #endif
 
   if (browser::GrabWindowSnapshot(window, &png_data->data(), rect)) {
+    DisplayVisualFeedback(rect);
     content::BrowserThread::PostTask(
         content::BrowserThread::FILE, FROM_HERE,
         base::Bind(&SaveScreenshot, is_logged_in, png_data));
@@ -92,3 +102,25 @@ void ScreenshotTaker::HandleTakePartialScreenshot(
 void ScreenshotTaker::HandleTakeScreenshot(aura::Window* window) {
   HandleTakePartialScreenshot(window, window->bounds());
 }
+
+void ScreenshotTaker::CloseVisualFeedbackLayer() {
+  visual_feedback_layer_.reset();
+}
+
+void ScreenshotTaker::DisplayVisualFeedback(const gfx::Rect& rect) {
+  visual_feedback_layer_.reset(new ui::Layer(ui::Layer::LAYER_SOLID_COLOR));
+  visual_feedback_layer_->SetColor(
+      SkColorSetA(SK_ColorWHITE, kVisualFeedbackLayerOpacity));
+  visual_feedback_layer_->SetBounds(rect);
+
+  ui::Layer* parent = ash::Shell::GetInstance()->GetContainer(
+      ash::internal::kShellWindowId_OverlayContainer)->layer();
+  parent->Add(visual_feedback_layer_.get());
+  visual_feedback_layer_->SetVisible(true);
+
+  MessageLoopForUI::current()->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(&ScreenshotTaker::CloseVisualFeedbackLayer,
+                 base::Unretained(this)),
+      base::TimeDelta::FromMilliseconds(kVisualFeedbackLayerDisplayTimeMs));
+}