Update from https://crrev.com/303153

cc/resources/one_copy_raster_worker_pool.cc

Index: cc/resources/one_copy_raster_worker_pool.cc
diff --git a/cc/resources/one_copy_raster_worker_pool.cc b/cc/resources/one_copy_raster_worker_pool.cc
index c803262f06bbb4e8b486948492359175bd4b87cc..a8b838e83908ff4dd1d215ac9223e39a937258d9 100644
--- a/cc/resources/one_copy_raster_worker_pool.cc
+++ b/cc/resources/one_copy_raster_worker_pool.cc
@@ -54,16 +54,10 @@ class RasterBufferImpl : public RasterBuffer {
   // Overridden from RasterBuffer:
   void Playback(const RasterSource* raster_source,
                 const gfx::Rect& rect,
-                float scale,
-                RenderingStatsInstrumentation* stats) override {
+                float scale) override {
     sequence_ = worker_pool_->PlaybackAndScheduleCopyOnWorkerThread(
-        lock_.Pass(),
-        raster_resource_.Pass(),
-        resource_,
-        raster_source,
-        rect,
-        scale,
-        stats);
+        lock_.Pass(), raster_resource_.Pass(), resource_, raster_source, rect,
+        scale);
   }
 
  private:
@@ -280,68 +274,61 @@ OneCopyRasterWorkerPool::PlaybackAndScheduleCopyOnWorkerThread(
     const Resource* dst,
     const RasterSource* raster_source,
     const gfx::Rect& rect,
-    float scale,
-    RenderingStatsInstrumentation* stats) {
-  CopySequenceNumber sequence;
+    float scale) {
+  base::AutoLock lock(lock_);
 
-  {
-    base::AutoLock lock(lock_);
-
-    int failed_attempts = 0;
-    while ((scheduled_copy_operation_count_ + issued_copy_operation_count_) >=
-           kMaxCopyOperations) {
-      // Ignore limit when shutdown is set.
-      if (shutdown_)
-        break;
+  int failed_attempts = 0;
+  while ((scheduled_copy_operation_count_ + issued_copy_operation_count_) >=
+         kMaxCopyOperations) {
+    // Ignore limit when shutdown is set.
+    if (shutdown_)
+      break;
 
-      ++failed_attempts;
+    ++failed_attempts;
 
-      // Schedule a check that will also wait for operations to complete
-      // after too many failed attempts.
-      bool wait_if_needed = failed_attempts > kFailedAttemptsBeforeWaitIfNeeded;
+    // Schedule a check that will also wait for operations to complete
+    // after too many failed attempts.
+    bool wait_if_needed = failed_attempts > kFailedAttemptsBeforeWaitIfNeeded;
 
-      // Schedule a check for completed copy operations if too many operations
-      // are currently in-flight.
-      ScheduleCheckForCompletedCopyOperationsWithLockAcquired(wait_if_needed);
+    // Schedule a check for completed copy operations if too many operations
+    // are currently in-flight.
+    ScheduleCheckForCompletedCopyOperationsWithLockAcquired(wait_if_needed);
 
-      {
-        TRACE_EVENT0("cc", "WaitingForCopyOperationsToComplete");
+    {
+      TRACE_EVENT0("cc", "WaitingForCopyOperationsToComplete");
 
-        // Wait for in-flight copy operations to drop below limit.
-        copy_operation_count_cv_.Wait();
-      }
+      // Wait for in-flight copy operations to drop below limit.
+      copy_operation_count_cv_.Wait();
     }
+  }
 
-    // Increment |scheduled_copy_operation_count_| before releasing |lock_|.
-    ++scheduled_copy_operation_count_;
+  // Increment |scheduled_copy_operation_count_| before releasing |lock_|.
+  ++scheduled_copy_operation_count_;
 
-    // There may be more work available, so wake up another worker thread.
-    copy_operation_count_cv_.Signal();
+  // There may be more work available, so wake up another worker thread.
+  copy_operation_count_cv_.Signal();
 
-    {
-      base::AutoUnlock unlock(lock_);
-
-      gfx::GpuMemoryBuffer* gpu_memory_buffer =
-          write_lock->GetGpuMemoryBuffer();
-      if (gpu_memory_buffer) {
-        RasterWorkerPool::PlaybackToMemory(gpu_memory_buffer->Map(),
-                                           src->format(),
-                                           src->size(),
-                                           gpu_memory_buffer->GetStride(),
-                                           raster_source,
-                                           rect,
-                                           scale,
-                                           stats);
-        gpu_memory_buffer->Unmap();
-      }
+  {
+    base::AutoUnlock unlock(lock_);
+
+    gfx::GpuMemoryBuffer* gpu_memory_buffer = write_lock->GetGpuMemoryBuffer();
+    if (gpu_memory_buffer) {
+      RasterWorkerPool::PlaybackToMemory(gpu_memory_buffer->Map(),
+                                         src->format(),
+                                         src->size(),
+                                         gpu_memory_buffer->GetStride(),
+                                         raster_source,
+                                         rect,
+                                         scale);
+      gpu_memory_buffer->Unmap();
     }
+  }
 
-    // Acquire a sequence number for this copy operation.
-    sequence = next_copy_operation_sequence_++;
+  pending_copy_operations_.push_back(
+      make_scoped_ptr(new CopyOperation(write_lock.Pass(), src.Pass(), dst)));
 
-    pending_copy_operations_.push_back(
-        make_scoped_ptr(new CopyOperation(write_lock.Pass(), src.Pass(), dst)));
-  }
+  // Acquire a sequence number for this copy operation.
+  CopySequenceNumber sequence = next_copy_operation_sequence_++;
 
   // Post task that will advance last flushed copy operation to |sequence|
   // if we have reached the flush period.