delete pipeline and unittests

Author: Kaushik Iska

ci/licenses_golden/licenses_flutter

@@ -574,9 +574,6 @@ FILE: ../../../flutter/shell/common/isolate_configuration.h
 FILE: ../../../flutter/shell/common/persistent_cache.cc
 FILE: ../../../flutter/shell/common/persistent_cache.h
 FILE: ../../../flutter/shell/common/persistent_cache_unittests.cc
-FILE: ../../../flutter/shell/common/pipeline.cc
-FILE: ../../../flutter/shell/common/pipeline.h
-FILE: ../../../flutter/shell/common/pipeline_unittests.cc
 FILE: ../../../flutter/shell/common/platform_view.cc
 FILE: ../../../flutter/shell/common/platform_view.h
 FILE: ../../../flutter/shell/common/pointer_data_dispatcher.cc

shell/common/BUILD.gn

@@ -90,8 +90,6 @@ source_set("common") {
     "layer_tree_holder.h",
     "persistent_cache.cc",
     "persistent_cache.h",
-    "pipeline.cc",
-    "pipeline.h",
     "platform_view.cc",
     "platform_view.h",
     "pointer_data_dispatcher.cc",
@@ -190,7 +188,6 @@ if (enable_unittests) {
       "canvas_spy_unittests.cc",
       "input_events_unittests.cc",
       "persistent_cache_unittests.cc",
-      "pipeline_unittests.cc",
       "shell_test.cc",
       "shell_test.h",
       "shell_test_external_view_embedder.cc",

shell/common/animator.h

@@ -14,7 +14,6 @@
 #include "flutter/fml/synchronization/semaphore.h"
 #include "flutter/fml/time/time_point.h"
 #include "flutter/shell/common/layer_tree_holder.h"
-#include "flutter/shell/common/pipeline.h"
 #include "flutter/shell/common/rasterizer.h"
 #include "flutter/shell/common/vsync_waiter.h"
 
@@ -82,8 +81,6 @@ class Animator final {
   void EnqueueTraceFlowId(uint64_t trace_flow_id);
 
  private:
-  using LayerTreePipeline = Pipeline<flutter::LayerTree>;
-
   void BeginFrame(fml::TimePoint frame_start_time,
                   fml::TimePoint frame_target_time);