ash: Avoid reloading already-resized custom wallpaper.

ash/desktop_background/wallpaper_resizer_unittest.cc

 // Copyright 2013 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 "ash/desktop_background/wallpaper_resizer.h"
 
 #include "ash/desktop_background/wallpaper_resizer_observer.h"
 #include "base/message_loop/message_loop.h"
 #include "content/public/test/test_browser_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 23 matching lines @@
   // Fill bitmap with data.
   for (int y = 0; y < h; ++y) {
     for (int x = 0; x < w; ++x) {
       const uint8_t component = static_cast<uint8_t>(y * w + x);
       const SkColor pixel = SkColorSetARGB(component, component,
                                            component, component);
       *(src.getAddr32(x, y)) = pixel;
     }
   }
 
-  return gfx::ImageSkia::CreateFrom1xBitmap(src);
+  gfx::ImageSkia image = gfx::ImageSkia::CreateFrom1xBitmap(src);
+  return image;
 }
 
 bool IsColor(const gfx::ImageSkia& image, const uint32_t expect) {
   EXPECT_EQ(image.width(), kTargetWidth);
   EXPECT_EQ(image.height(), kTargetHeight);
   const SkBitmap* image_bitmap = image.bitmap();
   SkAutoLockPixels image_lock(*image_bitmap);
   return *image_bitmap->getAddr32(0, 0) == expect;
 }
 
@@ skipping 12 matching lines @@
 
   gfx::ImageSkia Resize(const gfx::ImageSkia& image,
                         const gfx::Size& target_size,
                         WallpaperLayout layout) {
     scoped_ptr<WallpaperResizer> resizer;
     resizer.reset(new WallpaperResizer(image, target_size, layout));
     resizer->AddObserver(this);
     resizer->StartResize();
     WaitForResize();
     resizer->RemoveObserver(this);
-    return resizer->wallpaper_image();
+    return resizer->image();
   }
 
   void WaitForResize() {
     message_loop_.Run();
   }
 
   virtual void OnWallpaperResized() OVERRIDE {
     message_loop_.Quit();
   }
 
@@ skipping 46 matching lines @@
   gfx::ImageSkia stretch = Resize(image, target_size, WALLPAPER_LAYOUT_STRETCH);
 
   gfx::ImageSkia tile = Resize(image, target_size, WALLPAPER_LAYOUT_TILE);
 
   EXPECT_TRUE(IsColor(center, kExpectedCenter));
   EXPECT_TRUE(IsColor(center_cropped, kExpectedCenterCropped));
   EXPECT_TRUE(IsColor(stretch, kExpectedStretch));
   EXPECT_TRUE(IsColor(tile, kExpectedTile));
 }
 
+TEST_F(WallpaperResizerTest, ImageId) {
+  gfx::ImageSkia image = CreateTestImage(
+      gfx::Size(kTestImageWidth, kTestImageHeight));
+
+  // Create a WallpaperResizer and check that it reports an original image ID
+  // both pre- and post-resize that matches the ID returned by GetImageId().
+  WallpaperResizer resizer(image, gfx::Size(10, 20), WALLPAPER_LAYOUT_STRETCH);
+  EXPECT_EQ(WallpaperResizer::GetImageId(image), resizer.original_image_id());
+  resizer.AddObserver(this);
+  resizer.StartResize();
+  WaitForResize();
+  resizer.RemoveObserver(this);
+  EXPECT_EQ(WallpaperResizer::GetImageId(image), resizer.original_image_id());
+}
+
 }  // namespace internal
 }  // namespace ash