GPU to raster rename, patch 2 (#17428)

diff --git a/fml/raster_thread_merger.cc b/fml/raster_thread_merger.cc
index e81eebb..718b41c 100644
--- a/fml/raster_thread_merger.cc
+++ b/fml/raster_thread_merger.cc
@@ -63,7 +63,7 @@
   lease_term_--;
   if (lease_term_ == 0) {
     bool success = task_queues_->Unmerge(platform_queue_id_);
-    FML_CHECK(success) << "Unable to un-merge the GPU and platform threads.";
+    FML_CHECK(success) << "Unable to un-merge the raster and platform threads.";
     is_merged_ = false;
     return RasterThreadStatus::kUnmergedNow;
   }
diff --git a/fml/raster_thread_merger.h b/fml/raster_thread_merger.h
index 847f7e3..1e12e3c 100644
--- a/fml/raster_thread_merger.h
+++ b/fml/raster_thread_merger.h
@@ -33,7 +33,7 @@
   void ExtendLeaseTo(size_t lease_term);
 
   // Returns |RasterThreadStatus::kUnmergedNow| if this call resulted in
-  // splitting the GPU and platform threads. Reduces the lease term by 1.
+  // splitting the raster and platform threads. Reduces the lease term by 1.
   RasterThreadStatus DecrementLease();
 
   bool IsMerged() const;
diff --git a/lib/ui/compositing/scene_host.cc b/lib/ui/compositing/scene_host.cc
index 83d0f56..8eb0ff5 100644
--- a/lib/ui/compositing/scene_host.cc
+++ b/lib/ui/compositing/scene_host.cc
@@ -188,8 +188,8 @@
     scene_host_bindings.emplace(std::make_pair(key, scene_host));
   };
 
-  // Pass the raw handle to the GPU thead; destroying a |zircon::dart::Handle|
-  // on that thread can cause a race condition.
+  // Pass the raw handle to the raster thread; destroying a
+  // |zircon::dart::Handle| on that thread can cause a race condition.
   raster_task_runner_->PostTask(
       [id = koid_,
        ui_task_runner =
diff --git a/lib/ui/painting/picture.cc b/lib/ui/painting/picture.cc
index e20f687..511e369 100644
--- a/lib/ui/painting/picture.cc
+++ b/lib/ui/painting/picture.cc
@@ -115,7 +115,7 @@
     delete image_callback;
   });
 
-  // Kick things off on the GPU.
+  // Kick things off on the raster rask runner.
   fml::TaskRunner::RunNowOrPostTask(
       raster_task_runner,
       [ui_task_runner, snapshot_delegate, picture, picture_bounds, ui_task] {
diff --git a/shell/common/shell.cc b/shell/common/shell.cc
index e660c54..9125f88 100644
--- a/shell/common/shell.cc
+++ b/shell/common/shell.cc
@@ -605,7 +605,7 @@
   // setup/suspension of all activities that may be interacting with the GPU in
   // a synchronous fashion.
   fml::AutoResetWaitableEvent latch;
-  auto gpu_task =
+  auto raster_task =
       fml::MakeCopyable([& waiting_for_first_frame = waiting_for_first_frame_,
                          rasterizer = rasterizer_->GetWeakPtr(),  //
                          surface = std::move(surface),            //
@@ -623,19 +623,20 @@
 
   // The normal flow executed by this method is that the platform thread is
   // starting the sequence and waiting on the latch. Later the UI thread posts
-  // gpu_task to the raster thread which signals the latch. If the GPU the and
-  // platform threads are the same this results in a deadlock as the gpu_task
-  // will never be posted to the plaform/raster thread that is blocked on a
-  // latch. To avoid the described deadlock, if the raster and the platform
-  // threads are the same, should_post_gpu_task will be false, and then instead
-  // of posting a task to the raster thread, the ui thread just signals the
-  // latch and the platform/raster thread follows with executing gpu_task.
-  bool should_post_gpu_task = task_runners_.GetRasterTaskRunner() !=
-                              task_runners_.GetPlatformTaskRunner();
+  // raster_task to the raster thread which signals the latch. If the raster and
+  // the platform threads are the same this results in a deadlock as the
+  // raster_task will never be posted to the plaform/raster thread that is
+  // blocked on a latch. To avoid the described deadlock, if the raster and the
+  // platform threads are the same, should_post_raster_task will be false, and
+  // then instead of posting a task to the raster thread, the ui thread just
+  // signals the latch and the platform/raster thread follows with executing
+  // raster_task.
+  bool should_post_raster_task = task_runners_.GetRasterTaskRunner() !=
+                                 task_runners_.GetPlatformTaskRunner();
 
   auto ui_task = [engine = engine_->GetWeakPtr(),                            //
                   raster_task_runner = task_runners_.GetRasterTaskRunner(),  //
-                  gpu_task, should_post_gpu_task,
+                  raster_task, should_post_raster_task,
                   &latch  //
   ] {
     if (engine) {
@@ -643,10 +644,10 @@
     }
     // Step 2: Next, tell the raster thread that it should create a surface for
     // its rasterizer.
-    if (should_post_gpu_task) {
-      fml::TaskRunner::RunNowOrPostTask(raster_task_runner, gpu_task);
+    if (should_post_raster_task) {
+      fml::TaskRunner::RunNowOrPostTask(raster_task_runner, raster_task);
     } else {
-      // See comment on should_post_gpu_task, in this case we just unblock
+      // See comment on should_post_raster_task, in this case we just unblock
       // the platform thread.
       latch.Signal();
     }
@@ -674,11 +675,11 @@
   fml::TaskRunner::RunNowOrPostTask(task_runners_.GetIOTaskRunner(), io_task);
 
   latch.Wait();
-  if (!should_post_gpu_task) {
-    // See comment on should_post_gpu_task, in this case the gpu_task
+  if (!should_post_raster_task) {
+    // See comment on should_post_raster_task, in this case the raster_task
     // wasn't executed, and we just run it here as the platform thread
     // is the raster thread.
-    gpu_task();
+    raster_task();
   }
 }
 
@@ -706,9 +707,9 @@
     latch.Signal();
   };
 
-  auto gpu_task = [rasterizer = rasterizer_->GetWeakPtr(),
-                   io_task_runner = task_runners_.GetIOTaskRunner(),
-                   io_task]() {
+  auto raster_task = [rasterizer = rasterizer_->GetWeakPtr(),
+                      io_task_runner = task_runners_.GetIOTaskRunner(),
+                      io_task]() {
     if (rasterizer) {
       rasterizer->Teardown();
     }
@@ -718,29 +719,29 @@
 
   // The normal flow executed by this method is that the platform thread is
   // starting the sequence and waiting on the latch. Later the UI thread posts
-  // gpu_task to the raster thread triggers signaling the latch(on the IO
-  // thread). If the GPU the and platform threads are the same this results in a
-  // deadlock as the gpu_task will never be posted to the plaform/raster thread
-  // that is blocked on a latch.  To avoid the described deadlock, if the raster
-  // and the platform threads are the same, should_post_gpu_task will be false,
-  // and then instead of posting a task to the raster thread, the ui thread just
-  // signals the latch and the platform/raster thread follows with executing
-  // gpu_task.
-  bool should_post_gpu_task = task_runners_.GetRasterTaskRunner() !=
-                              task_runners_.GetPlatformTaskRunner();
+  // raster_task to the raster thread triggers signaling the latch(on the IO
+  // thread). If the raster and the platform threads are the same this results
+  // in a deadlock as the raster_task will never be posted to the plaform/raster
+  // thread that is blocked on a latch.  To avoid the described deadlock, if the
+  // raster and the platform threads are the same, should_post_raster_task will
+  // be false, and then instead of posting a task to the raster thread, the ui
+  // thread just signals the latch and the platform/raster thread follows with
+  // executing raster_task.
+  bool should_post_raster_task = task_runners_.GetRasterTaskRunner() !=
+                                 task_runners_.GetPlatformTaskRunner();
 
   auto ui_task = [engine = engine_->GetWeakPtr(),
                   raster_task_runner = task_runners_.GetRasterTaskRunner(),
-                  gpu_task, should_post_gpu_task, &latch]() {
+                  raster_task, should_post_raster_task, &latch]() {
     if (engine) {
       engine->OnOutputSurfaceDestroyed();
     }
     // Step 1: Next, tell the raster thread that its rasterizer should suspend
     // access to the underlying surface.
-    if (should_post_gpu_task) {
-      fml::TaskRunner::RunNowOrPostTask(raster_task_runner, gpu_task);
+    if (should_post_raster_task) {
+      fml::TaskRunner::RunNowOrPostTask(raster_task_runner, raster_task);
     } else {
-      // See comment on should_post_gpu_task, in this case we just unblock
+      // See comment on should_post_raster_task, in this case we just unblock
       // the platform thread.
       latch.Signal();
     }
@@ -750,11 +751,11 @@
   // surface is about to go away.
   fml::TaskRunner::RunNowOrPostTask(task_runners_.GetUITaskRunner(), ui_task);
   latch.Wait();
-  if (!should_post_gpu_task) {
-    // See comment on should_post_gpu_task, in this case the gpu_task
+  if (!should_post_raster_task) {
+    // See comment on should_post_raster_task, in this case the raster_task
     // wasn't executed, and we just run it here as the platform thread
     // is the raster thread.
-    gpu_task();
+    raster_task();
     latch.Wait();
   }
 }