cc: Simplify task and its derived classes.

cc/raster/tile_task_runner.cc

Index: cc/raster/tile_task_runner.cc
diff --git a/cc/raster/tile_task_runner.cc b/cc/raster/tile_task_runner.cc
index 50e8805d938136719e73c7c4b191144035d55180..0c1f1aaa6e860e8c5ebd6cee554b27a7148a395c 100644
--- a/cc/raster/tile_task_runner.cc
+++ b/cc/raster/tile_task_runner.cc
@@ -7,54 +7,6 @@
 
 namespace cc {
 
-TileTask::TileTask() : did_schedule_(false), did_complete_(false) {
-}
-
-TileTask::~TileTask() {
-  DCHECK(!did_schedule_);
-  DCHECK(!did_run_ || did_complete_);
-}
-
-void TileTask::WillSchedule() {
-  DCHECK(!did_schedule_);
-}
-
-void TileTask::DidSchedule() {
-  did_schedule_ = true;
-  did_complete_ = false;
-}
-
-bool TileTask::HasBeenScheduled() const {
-  return did_schedule_;
-}
-
-void TileTask::WillComplete() {
-  DCHECK(!did_complete_);
-}
-
-void TileTask::DidComplete() {
-  DCHECK(did_schedule_);
-  DCHECK(!did_complete_);
-  did_schedule_ = false;
-  did_complete_ = true;
-}
-
-bool TileTask::HasCompleted() const {
-  return did_complete_;
-}
-
-ImageDecodeTask::ImageDecodeTask() {
-}
-
-ImageDecodeTask::~ImageDecodeTask() {
-}
-
-RasterTask::RasterTask(ImageDecodeTask::Vector* dependencies) {
-  dependencies_.swap(*dependencies);
-}
-
-RasterTask::~RasterTask() {
-}
 
 bool TileTaskRunner::ResourceFormatRequiresSwizzle(ResourceFormat format) {
   switch (format) {