cheets: implement cros side of WallpaperManagerService.

chrome/browser/chromeos/arc/arc_wallpaper_service.cc

 // Copyright 2016 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/arc_wallpaper_handler.h"
+#include "chrome/browser/chromeos/arc/arc_wallpaper_service.h"
 
 #include <string>
 #include <utility>
 #include <vector>
 
+#include "ash/shell.h"
+#include "ash/wallpaper/wallpaper_controller.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
+#include "base/task_runner_util.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
+#include "components/arc/arc_bridge_service.h"
 #include "components/signin/core/account_id/account_id.h"
 #include "components/user_manager/user_manager.h"
 #include "components/wallpaper/wallpaper_files_id.h"
 #include "components/wallpaper/wallpaper_layout.h"
 #include "content/public/browser/browser_thread.h"
+#include "ui/gfx/codec/png_codec.h"
+#include "ui/gfx/image/image.h"
 #include "ui/gfx/image/image_skia.h"
+#include "ui/gfx/image/image_util.h"
 
 using user_manager::UserManager;
 
 namespace arc {
 
 namespace {
 
 constexpr char kAndroidWallpaperFilename[] = "android.jpg";
 
 // Sets a decoded bitmap as the wallpaper.
@@ skipping 19 matching lines @@
       account_id, wallpaper_files_id, kAndroidWallpaperFilename,
       wallpaper::WALLPAPER_LAYOUT_STRETCH, user_manager::User::CUSTOMIZED,
       image, update_wallpaper);
 
   // TODO(crbug.com/618922): Register the wallpaper to Chrome OS wallpaper
   // picker. Currently the new wallpaper does not appear there. The best way to
   // make this happen seems to do the same things as wallpaper_api.cc and
   // wallpaper_private_api.cc.
 }
 
+std::vector<uint8_t> EncodeImagePNG(const gfx::ImageSkia image) {

[hidehiko, 2016/09/07 01:16:25]

nit: EncodeImagePng.

cf) https://google.github.io/styleguide/cppguide.html#Function_Names
"Prefer to capitalize acronyms as single words (i.e. StartRpc(), not
StartRPC())."

[Muyuan, 2016/09/07 02:50:47]

Acknowledged.

+  std::vector<uint8_t> result;
+  gfx::PNGCodec::FastEncodeBGRASkBitmap(*image.bitmap(), true, &result);
+  return result;
+}
+
 }  // namespace
 
-ArcWallpaperHandler::ArcWallpaperHandler() = default;
+// TODO(muyuanli): This will be removed once SetWallpaperDelegate class is
+// removed.
+SetWallpaperDelegate* SetWallpaperDelegate::instance_ = nullptr;

[hidehiko, 2016/09/07 01:16:25]

Could you define this as a part of components/arc/libarc.a?
Even for the very short-term solution, I'd like to keep the consistency of the
lib definition.

IMHO, define the var somewhere in components/arc/libarc.a, and introducing
static SetWallpaperDelegate::SetInstance(...) is fine.

[Muyuan, 2016/09/07 02:50:47]

OK. Made it part of ArcIntentHelper temporarily. 

 
-ArcWallpaperHandler::~ArcWallpaperHandler() {
+ArcWallpaperService::ArcWallpaperService(ArcBridgeService* bridge_service)
+    : ArcService(bridge_service), binding_(this) {
+  arc_bridge_service()->wallpaper()->AddObserver(this);
+  DCHECK(!instance_);
+  instance_ = this;
+}
+
+ArcWallpaperService::~ArcWallpaperService() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   // Make sure the callback is never called after destruction. It is safe to
   // call Cancel() even when there is no in-flight request.
   ImageDecoder::Cancel(this);
+  arc_bridge_service()->wallpaper()->RemoveObserver(this);
+  DCHECK(instance_ == this);
+  instance_ = nullptr;
 }
 
-void ArcWallpaperHandler::SetWallpaper(std::vector<uint8_t> jpeg_data) {
+void ArcWallpaperService::OnInstanceReady() {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  mojom::WallpaperInstance* wallpaper_instance =
+      arc_bridge_service()->wallpaper()->instance();
+  if (!wallpaper_instance) {
+    LOG(ERROR) << "OnWallpaperInstanceReady called, "

[hidehiko, 2016/09/07 01:16:25]

Could you use LOG(DFATAL) instead?
This is unexpected situation. So, on Debug build, crashing will be better.

[Muyuan, 2016/09/07 02:50:47]

Acknowledged.

+               << "but no wallpaper instance found";
+    return;
+  }
+  wallpaper_instance->Init(binding_.CreateInterfacePtrAndBind());
+}
+
+void ArcWallpaperService::SetWallpaper(mojo::Array<uint8_t> png_data) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  ImageDecoder::Cancel(this);
+  ImageDecoder::StartWithOptions(this, png_data.PassStorage(),
+                                 ImageDecoder::ROBUST_PNG_CODEC, true);
+}
+
+void ArcWallpaperService::GetWallpaper(
+    const base::Callback<void(mojo::Array<uint8_t>)>& callback) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  ash::WallpaperController* wc =
+      ash::Shell::GetInstance()->wallpaper_controller();
+  gfx::ImageSkia wallpaper = wc->GetWallpaper();
+  base::PostTaskAndReplyWithResult(
+      content::BrowserThread::GetBlockingPool(), FROM_HERE,
+      base::Bind(&EncodeImagePNG, wallpaper), callback);
+}
+
+void ArcWallpaperService::SetWallpaperJPEG(

[hidehiko, 2016/09/07 01:16:25]

Ditto. "SetWallpaperJpeg"

[Muyuan, 2016/09/07 02:50:47]

Acknowledged.

+    const std::vector<uint8_t>& jpeg_data) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   // If there is an in-flight request, cancel it. It is safe to call Cancel()
   // even when there is no in-flight request.
   ImageDecoder::Cancel(this);
   ImageDecoder::StartWithOptions(this, std::move(jpeg_data),
                                  ImageDecoder::ROBUST_JPEG_CODEC, true);
 }
 
-void ArcWallpaperHandler::OnImageDecoded(const SkBitmap& bitmap) {
+void ArcWallpaperService::OnImageDecoded(const SkBitmap& bitmap) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   SetBitmapAsWallpaper(bitmap);
 }
 
-void ArcWallpaperHandler::OnDecodeImageFailed() {
+void ArcWallpaperService::OnDecodeImageFailed() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   LOG(ERROR) << "Failed to decode wallpaper image.";
 }
 
 }  // namespace arc